iTunes has its faults... but it does what Apple intends, easy use. Plug iPod in away you go.... album art, ratings ect all very easy.
If you have a large collection say over (21,000 tracks
) Its nice and easy to browse though the album covers....
Windows Media player is worse really.... Winamp the best, but not user freindly.
Amarok will get all your album art automatically from the net, just one click away.
Oh and iTunes won't play a single track of my 100+ Gb collection, as they're all in FLAC and unlike any decent media player which supports plugins, if Apple doesn't give a format their blessing, then you're not playing it.
Yes Windows Media Player sucks royally (Media Player Classic is a perfect example of less being more), but it's a very poor benchmark to aim for anyway.
Personally I use Winamp with the FLAC plugin on Windows, and Amarok on Mac or *nix. I don't have an iPod, don't like them for the very reasons described above -- i.e. they're full of artificial restrictions. Although I believe there are hacked firmwares out there for some models that allow them to work in a more consumer-friendly manner.
Oh and by decent quality MP3 player I should have said "decent quality solid-state portable music player"

. I agree MP3 sucks and is well past its retirement date, personally I always use FLAC to rip CDs at home, and where space is a premium over sound quality I'll use Ogg Vorbis if possible and failing that AAC.