Is Bono a tenor or a baritone?

Technically, someone who can sing a tenor part only in falsetto is not
a tenor. I'm a bass, but I have a pretty good falsetto and can sing
most tenor parts. My falsetto, like that of most nonprofessionals, is
fairly thin. However, serious singers can train to strengthen their
falsetto, and with time they can move smoothly from their normal
register into the falsetto without a substantial loss of volume and
tone quality. A true tenor can crank out notes well above the middle C
without going into falsetto.

Here is a decription of the voice parts, written from an opera perspective:

http://www.lyricoperaofwaco.org/education/voices/

"TENOR 
The highest range of the male voice is the tenor. Tenors also have the
shortest range- usually from E flat below to A flat above middle C.
Tenors often have a lead role as the lover, leader, or hero.
Countertenors are artists who use either falsetto or a naturally light
and heady tenor voice to sing in the female alto range.

BARITONE 
The middle range of the male voice is the baritone, whose range
extends from A flat an octave and 1/3 below middle C up to E flat
above middle C. The best baritones have the freedom to move into the
higher notes and also descend to the rich lower notes. Baritones play
roles from kings to devils, and their lead roles lean to the dark
side."

http://composers21.com/compdocs/ferneyhb.htm

It sounds like Bono is a baritone who has trained his voice such that
he can hit tenor notes in falsetto. Such is the situation for many
rock stars (http://en.wikipedia.org/wiki/Countertenor), though
explaining this fact to nonexperts can be irritating or embarrassing,
and most singers just call themselves (or accept being called) tenors.

While opera allows for many different technical terms for voice parts,
outside of opera, most singers are less picky about the terms. Singers
like Bono can be called ?baritone falsettos? or ?falsettists,? though
there is some disagreement among purists about what constitutes
either. That?s a discussion I?ll leave to college music majors looking
to pick a fight.

Check the following links that reference baritones who sing in the falsetto.

http://www.aristarec.com/aristaweb/CrashTestDummies/info.html
http://www.reggiewatts.com/about.aspx
http://www.ptloma.edu/music/MUH/baroque/baroquevocrange/baroquevocrange.htm
http://www.network54.com/Forum/thread?forumid=108991&messageid=1108517050&lp=1108762070
http://www.spebsqsa.org/web/groups/public/documents/pages/pub_cb_00180.hcsp

V

There doesn't appear to be a consensus of opinion:

"Bono allegedly picked up his nickname from the Latin Bono Vox (good
voice), but it was initially his charismatic stage presence that
helped U2 gain a reputation for live performance. U2's relentless
touring schedule quickly boosted his vocal prowess, however, and by
the time of the band's groundbreaking 1983 War release, Bono had
developed a soaring tenor. Within four years it would become one of
the most recognizable voices in popular music."

http://www.mp3.com/bono/artists/43380/biography.html

"This documentary takes an unprecedented look at the personal history
of rock legend Bono, known as much for his idealism and activism with
regards to a plethora of worthy causes as for his striking tenor
voice, strong lyrical talent, and charisma as the frontman for Irish
band U2."

http://movies.yahoo.com/shop?d=hv&id=1808609533&cf=info&intl=us

" In between the bitter humor of "Seconds," he breaks into joyous
flights of wordless melody, his voice soaring in multi-tracked
polyphony over the song's slippery rhythms. "Surrender" is lighter
still, thanks to its airy melody and the Edge's coolly sustained
guitar. In fact, this song is the one instance where the music says
more than lyrics ever could, because hearing Bono's blissful tenor
floating over the backing vocals."

http://grunschev.com/collectorz/details/13020.html 

"Imbued with arena-ready drama, Bono's liquid falsetto and gritty
baritone convey the humble yearning and lucid emotion of an Everyman,
not a messiah."

http://www.u2station.com/documents/atyclb/albumreviews/usatoday_review.txt

"A classic U2 ballad, as always the third track on their albums.
Written for Bono's father ('You´re the reason why the opera is in
me...'), Edge is singing the chorus in falsetto, joined by Bono's
fragile baritone."

http://www.u2tour.de/specials/htdaab_prelistening/index_EN.php

"The first line of the first song on 'All That You Can't Leave Behind'
sets the tone. 'Beautiful Day' opens with a pulsing heartbeat rhythm,
soaring-yet-understated keyboards and Bono's subtle baritone leading
into one of his classic images: 'The heart is a bloom, shoots up
through the stony ground."

http://html.channel3000.com/sh/entertainment/stories/entertainment-20001107-150922.html

"On a side note, I have to disagree with the person above who
described Bono of U2 as a baritone. No way! He's definitely a tenor,
and a high one at that. On 'Pride in the Name of Love,' that's a high
B he's hitting. In fact, the whole chorus takes place between the E
above middle C and the high B. Only a tenor could sing consistently in
that range. Then, on 'Bad,' Bono actually hits a high C# when he sings
the words 'wide awake.' It's strained and gravelly, but boy is it
high. On the other hand, those songs are from the mid-1980s. Bono
doesn't sing in that range as much anymore."

http://www.2blowhards.com/archives/001179.html

There are physiological and other factors involved in determining
range.  In classical contexts, a predominance of "head resonance" which
involves maintaining a lower position of the larynx (thereby creating
room in the pharynx for higher frequencies and more complex overtone
formants) was "de riguer".  The advent of popular music made acceptable
a pushing of the chest register at higher pitches than formerly
acceptable (sounding more like speech) which involves a more highly
positioned larynx (less overtone).  Many baritones of today have
developed a complex falsetto that sounds like "tenor" because of the
additional chest tones.  There are some baritones that train into
"heroic tenors" by virtue of their physical capabilities, possibly
attributable to longer vocal tract, consistentcy of tissue, breath
pressure capacity and overall coordination (that is, TALENT)  It's
important to find the center of your voice and you will be able to
branch out upward and lower in the range as coordination is achieved
through practice and time.  A tenor CANNOT sing a low A.  However, a
baritone in today's world effortlessly nail a lower A (A2) AND can ALSO
easily nail a stratospheric F# above C5.  Listen to Chris Cornell
(formerly of Soundgarden, now Audioslave).  He's a bona fide baritone
that can soar way up there. as does Scott Weiland, Eddie Veder, Bono
and many more!  But they never sound like Steve Perry (Journey) does up
there- that's a whole different translucent timbre reserved only for
true tenor.  Not necessarily better- just a different timbre.