Yeah, I was just looking for a quick way to always be able to keep my main iTunes Mac running and if I wanted to stream anything on my library but not on my iPad, to be able to do this but it sounds like from the replies that Apple overlooked the ability to do this, which is strange considering it's a home wifi network and you know the iPad has Bonjour installed so why did Apple essentially lock an $800 portable tablet out of it's own closed in ecosystem.
The other thing that's puzzling is that I have a MobileMe account that pre-iPad sync'd two Macs and an iPhone 3GS. Now, if you belong to MobileMe, you can see your "sync devices" to make sure they are participating in the "cloud" for your account. The iPad again locks itself out of this very helpful info both by not including a MobileMe Admin support within the iPad's "Preferences" App but also when wired directly to the Mac for syncing, the iPad never shows up in "Snyc Devices" in the iTunes Preferences tab. The reason this was an issue for me is that because the iPad is not included, it chooses itself whether or not to Merge MobileMe Data or to completely replace it from the cloud.
It's very frustrating, it feels very rushed that Apple has so much hype behind the iPad and now that I have one it takes a great deal of more managing to make sure the data is moving between other Apple devices the way I want it. The iPhone is much easier to manage.
