It's pretty apparent at this point that nobody ever knows when updates will be released. I don't understand why this couldn't have been asked as a response to the initial news thread instead of creating a new post.
My guess, and it's just a guess, is that we'll see a big update (maybe 8.1) announced with the new iPads at an event in October. Right now the rumors are saying the event will take place on the 21st.
The last few .1 OS's were available in beta to developers a few weeks before they were officially released, so if 8.1 really will be released at the end of October then we should see 8.1 betas pretty soon. Again, though, this is all purely speculation.