1. Dave Matthews and all his clones (especially his clones). Anyone that strums an acoustic guitar, switching between falsetto and lower registers during verses and has a "groove" feel to it instantly puts me out. Includes Jason Mraz, Mayer, Powter, & James Blunt.
2. Radiohead. Sorry. zzzzzzzzz
3. Former alt bands that went pop - Counting Crowes, Wilco, Matchbox 20 (debatable I know), Goo Goo Dolls, REM & The Wallflowers. I'm all for growing and expanding as an artist, and have never had an issue with "selling out" but if all you're going to do is regurgitate pop formulae then I'm gonna tune you out.
4. Half of Ryan Adams' stuff. I love half, hate half. I guess if you're that prolific though, that's bound to happen. But if I hear him with nothing more than an acoustic guitar and that silly high, but not quite falsetto voice of his one more time I just may... take a nap.
5. R&B solo artists. Maybe it's just me but the Mary J. Blige's, Beyonce's, R. Kelly's, Usher's & Mariah Carey's of the industry bore me to tears. The voices are all the same, the songs are all the same, the subject matter is all the same. I get it, you're very talented singers in a traditional sense. But do something to stand out or I can't be bothered.