The only thing about tall grass and desert shrubs are that they won't appear in areas you've already explored. So you're out of luck if you don't have any seeds yet and want some.
Personally, I think (considering maps crash the server I play on) that Multiplayer Nether has been the most substantial update. Spent all afternoon and all night yesterday (and a small part of this morning, technically) building myself a sinister-looking castle over a lava lake. It took me all of my cobblestone and a good amount of glass and Netherrack, and I still need to put in ~30 iron doors, but so far, so good.