Apple has already stated they will discuss the following:

Mac OS 10.7 Lion
iOS 5
iCloud

Plenty is already known about Leopard but the others have been discussed only in terms of rumors from press to blogs.

Part of iCloud is supposed to be a music streaming service from Apple to stream your own tunes. The latest rumor is it will cost $25 per year. That amount seems low and may not even make most people think twice. For me however, the service, as rumored, doesn't seem like it's worth any more than $0 however.

I already have all my music on my network. I can already take as much as I need with me. If I use internet bandwidth to stream the same music I'm already going to be paying for the pipes. Paying Apple (or Google) only to increase my expenditure with my ISP to play music I've already got locally just doesn't make any sense. It's simply not something I find compelling at all.

Right now I don't actually have any mobile data, having had to cancel the iPad plan I was using with my iPhone as it stopped working. The tech department at Bell couldn't give me an explanation and tried a few things to get it going, but all I ever got was connection failure messages on the phone. It's not worth it to me to pay one of the carriers for an iPhone-specific plan for voice, let alone data. It's just way too much money per month compared to my actual usage. And if I were to focus on using more simply to try and justify the expense, it would probably backfire and I'd only end up having to spend more for even greater limits.

I'm still interested to see what might become of MobileMe and whether or not it will be free, even though I might not be able to take advantage of it from my iPhone.