Apple has scheduled an event Tuesday. The main purpose of that event is to launch new iPod Nano and Touch models. But it's also expected that iTunes 8 will be released with features like a Pandora-like Genius, new visualization, and grid view.
But more importantly iPhone OS 2.1 should also be released to coincide with the expected release of the notification service scheduled to be released in September. With the iPhone OS 2.1 and notification service I would expect to see Apple release a mobile version of iChat. Or at least I would hope to see it. This was rumored from the start for the 2.0 release but it seems that the notification service was not ready for that release in July.
We'll see what Steve has in store for us Tuesday.