I'm not sure if the lala acquisition would help with this, or if this is something Apple is even interested in doing, but I had a really great idea a few days ago that Apple could incorporate into iPods:
Stream your whole library to your iPhone/iPod touch.
My music library is currently sitting at 30GB. Even if I got the 32GB touch or Iphone, I'd want to save some space for application data, pictures, videos, etc. So why not sync, say, 10% of my newest or most highly played or rated songs to the device, and make the rest of my library available, stramed right from my Computer to the device?
For it to work, it would have to be seamless. So if I'm online, it will let me browse my entire library. If I listen to a song, sync it locally. If I'm online, only show me the songs that are synced locally.
Even though this would be great, I have a feeling the record companies might shit themselves for some reason if this was done. Best case scenario, Apple would only make your 'purchased' songs available for streaming. Because obviously anything in iTunes that I didn't buy from ITMS must have been pirated, right Apple?