Venerable technology website Ars Technica has the details. Here are the highlights:

Hardware
- iPod Nano gets a video camera, an FM Radio, a pedometer, built-in Nike+iPod (this is sold separately), a speaker and voice-memo recording
- iPod touch gets the hardware and graphics muscle of the iPhone 3G S, gets a new 64GB model, but not the widely expected camera, disappointing nearly everyone
- iPod shuffle (the buttonless wonder) is now available in 5 colours
Software
- iTunes 9 released (now at a bloated 88MB), can now share your music collection across your home computers, can now rearrange applications on your iPod touch/iPhone by drag and drop.
- iTunes Store redesigned. This is irrelevant for those of you in India.
Starware
- Steve Jobs back in action after liver transplant