Unfortunately I don't have access to the beta and would like to know what the current size of the patches are. If I understand it correctly the pre-download version is build 8370, which is patch12? I hope we can simply add the sizes of the patches after that a get to the size of the patch on day of release.
Hopefully Blizz will allow us to start downloading an 0-day patch before the game goes live. Would be a terrible first experience if 12am PDT comes and we're all downloading a 1 gig patch and depending on what your download speed is, that can be a pain.
I believe it's very likely we see something along the lines of 500+ mb. They've probably left some work to be done in this last month (like fixing items, artwork, some graphical glitches, and system bugs that are still being found in the beta).