Yeah but it's got a newer kernel in it. Which is good for Skylake CPU / IGP support. Already on 15.04 on this laptop. Which has been working OK.
In specific the Beta2 of 15.10 is the last major beta release. After that is about 1 month of locking things down, for the release on 22 October. So that means there won't be any more significant RC releases left to come. Just fixes via ubuntu software update. I'm happy with that situation.
Last time I upgraded from 14.10 --> 15.04 and it was fine. But might have left some un-needed cruft behind from previous. So that's why I'm hoping to start on 15.10.
We shall see. If any issues, then can always roll back one and reinstall as 15.04.