I have never been a fan of the "genretization" of music, especially at the artist level.

I imagine that if you listen to an individual track, you might be able to say this is a "jazzy sounding tune" or something but to lump an artist in a particular category is amazingly short sighted - and to base your listening upon these generalizations can severely limit your exposure to some amazing work.
While artists like The Allman Brothers Band get placed in the horrendous (and meaningless) Southern Rock category, others are categorized based upon a single hit, and others can't seem to shake an early classification despite their maturity and expanding sound.
So here are some examples I've come across in my travels that I think are particularly amusing or erroneous
10cc - Soft Rock, Soft Pop
Sure, "I'm Not In Love" is a sappy lite radio staple - but if you can say anything about this band is that they can't be taken at face value. The tongue in cheek love song is just one song in an eclectic catalog that includes "I'm Mandy Fly Me", "Life is a Minestrone", the reggae tinged "Dreadlock Holiday" and my personal favorite "Feel The Benefit". Sappy sure, but this is a band that doesn't deserve being lumped alongside The Little River Band or {shudder} Orleans or Looking Glass....
Chicago - Soft Rock, Soft Pop
OK - I'll give you that this once stellar band has brought this upon themselves with the mindless 80's ballads - but to dismiss them upon this categorization ignores the brilliance and sheer energy of their early albums. Back when Terri Kath was still alive and Peter Cetera still played Bass guitar, this band could kick out a jam.
Genesis - Pop
Same deal here I guess. Later work is indeed perfect for the lite rock office worker crowd, but to ignore the progressive rock genius of their earlier work based upon this is well, just wrong. Put on "Supper's Ready" and watch the secretaries squirm....
Lyle Lovett - Country
This one is particularly bothersome to me. Anyone who calls Lyle Lovett a country artist is doing him a tremendous disservice and ignoring the obvious blues, jazz, folk, bluegrass, big band, and other influences that make him one of the greatest singer song writers of our time.
Wilco - Country
Yahoo just recently changed this one to the generic Adult Alternative category. Neither can capture the diverse sounds that this band creates. Sure - A.M. may have had a twangy feel but to lump these guys into any single category is pointless.
Allman Brothers - Southern Rock, Jam Band
I am going to just ignore the Southern Rock tag, it doesn't even deserve a response. And to paraphrase a quote by Gregg Allman - The Allman Brothers aren't a jam band - they are a band that jams.
Go see 'em live - you'll agree
I'm sure there are hundreds more - what examples have you seen? Share them in the comments.