According to inside sources at Ars Technica, the “Let’s Rock” Apple private invite only event will include the much anticipated release of iPhone firmware 2.1.
Among the list of expected improvements:
– a solution to apps repeatedly crashing the iPhone (and sometimes resulting in the Apple Screen of Death)
– preliminary support for push technology allowing apps to get background info
– new GPS functionality — possibly allowing background GPS notification, as intimated by loopt
One disturbing aspect:

“We were told that, aside from what we already know about iPhone 2.1 from leaked info on the web, there are other parts to 2.1 that were specifically removed from developer seeds in order to keep them secret from the world.”

As usual, Apple is carefully managing the release of information…