Gruber concurs with the widely expected faster processor, doubled ram, doubled storage, and video recording. He expects the price points to remain the same with the 16GB selling for $199 and the 32GB selling for $299.
He has heard that new hardware's code name is the iPhone 3GS. Although he doesn't know what the S stands for, Gruber thinks its likely this will be the official name.
Also mentioned is that the new iPhone should see a 15-20 percent improvement in battery life.
Gruber expects the iPhone 3G to stick around a bit longer at the $99 price point. This would make sense given that there have been several reports from established sources pointing to a cheaper iPhone.
As for design changes he expects minimal differences but with some new cool factor to freshen things up a bit.
The article has a lot more to say about Snow Leopard, the Marble interface and the tablet...
[Possible Back Case to the New iPhone]