The only + Ive found using iTunes was the multithredded ripping (faster).
The downsides are.
Running in the background when not using it, I had to hack it out of the registry along with Quicktime so drivers and whatnot would not be running in the background on boot up.
Cant get cover art unless your part of iTunes online, F' that, Media player will look for it and at least let you import it if you have an image.
As mentioned above you cant play via catagory type, Album, Type ect.
Slow all around.
Wont auto add new songs or even have a button to rescan, Have to delete its catalog manualy restart and wait hrs while it rescans the whole library again.
Wont use album art from other rip sorces.
Cant find songs it just listed in your library (has a + next to it, You follow the path it has, Its there but it still cant see it.
Corrupting the library (In win XP and win7-64) Nothing like having to re-rip 6000+ again and again (now burned down to DVDs)
The lockup on any song it thinks (It thinks is the key word) might be corrupted or pirated.
I personaly cant find a way to dual pane for drag and drop, have to constanly switch between ipod and library to see what I already have on it.
Things I hate about my ipod (I belive its a shuffle 2"x3", 3rg gen I cant remember what mdl it is)
Doesnt show cover art except 2 cd's when itunes shows them.
Cant delete songs, wtf is up with that.
The random song play is wierd, I hear patters and themes in its playing (like a two for tuesday).
Random will not play all songs.
The touch ring sensor is whack sometimes or maybe its sensative to ghost, Nothing like having your music volume go up and down randomly.
Oh yeah, It will not play or will jump from songs it thinks (Key word here is thinks) might be pirated or corrupted (even though I just ripped it with iTunes).
I find that Apple has to make iTune propriatary is because no one would use it at all if they had other choices.