If you don't like the new white color, you can switch to the dark version:
Open preferences of iTunes (Cmd+,) and select "Dark" for "Gridview" under "General". Hope the names are fine, cuz I'm not running the English version of iTunes.

iTunes 9 is UGLY!

If you don't want to downgrade to version 8:
Change the ugly version 9 skin to version 8:
http://www.libertypages.com/clarktech/?p=813 (download iTunes.rsrc.2.zip)

To remove the iTunes Store links from your lists:
Open Terminal and type (copy/paste)
defaults write com.apple.iTunes show-store-arrow-links -bool FALSE

btw, I updated to 9.0.1 and I had to download the skin again.

iTunes 9 is just butt-ugly. White background in icon view is a joke...

New iTunes 9 is slow and buggy as hell. I regret updating

iTunes 8.1 offers a major speed improvement for me, as promised. I am running iTunes on a 4-year old 1.8 Ghz PPC G5 iMac with 1.5 GB RAM and was thinking of replacing the computer b/c iTunes was really getting slow with a 125GB music library and several dozen smart playlists. But it is now zippy and responsive. Very impressive upgrade.

Note: for those of you using Doug's apple scripts: some scripts require fixing for compatibility with iTunes 7.7.1.

dougscripts.com

My mistake: actually the 'unsubscribe' button in iTunes does what I want. (I thought it would remove the podcast subscription and items entirely, as in Google Reader.)

I prefer Miro for video podcasts, as I can tell it not to auto-download new items. I didn't find this option on iTunes, and I didn't like it filling my drive while I didn't have time to watch the already downloaded items.
Miro and iTunes both can resume playback of a podcast item.

There's an interesting discussion about audio players for Mac OS X on hydrogenaudio.

I have a very awkward feeling, that iTunes is getting more and more sluggish for each iteration. Makes me wonder if they are deliberately making it so, in order to have me purchase a newer Mac. (I'm still using a Mac dual 2.5 Ghz a la 2004.)