Theres a lot of good points here, and i am in the same situation as the OP. I have concluded this, 16gb touch is the way to go.
If you look at the prices, the 16gb seems like best band for your buck. I have 20+GB of music, and then a huge amount more of movies.
I figure that i can cut down to about 12 GB of good music i currently listen to, and toss on some movies or TV shows im into at the moment. changing up the content is a pain when its pick and choose, so we all want to minimize that. So i think unless you can easily afford the 32 the 16 is where its at because with the SDK who knows what will happen. I'm hoping i can use this as a PDA and have a gig or two of documents and apps on there.
I vote 16. Its the logical choice unless you can afford the 32, because naturally you would want everything all the time just incase your in one of those 'moods' where you need a song, or album and its not there.. thats a depressing time i find.
Bon Chance!