Win8 RTM vs Retail?

Hey everyone. I have a quick question. Is there any difference between the RTM available now and the copy of Windows 8 that's going to be available in October? I've been confused because some people in the comments make it sound like it's an identical copy to what's being released in October, and other say that there may be minor changes between now and October. So I'm confused about what's the truth. I'd like to go ahead and install Windows 8 "for real" on my computer, but if the RTM isn't the same, I'll have to keep it on my small test partition. Thanks for the help!