Duff-Man says...not to berate or make light of the OP, but there's an easy lesson to be learned here. Any developer with some common sense is going to install a beta OS on a separate partition or disc to do their testing. Those that d/l from unauthorized websites and install over their existing stuff are playing with fire and imho get just what they deserve - play with fire and get burned.
Use your heads folks. If you really must grab a beta when your not a dev (or even if you are) then at least do so with appropriate caution, and if you're not set up to do so the just wait for the release and save yourself some aggravation. I'm as tempted as many to try out the latest - and admittedly have done so in the past (though not in years)...caution and smarts, when it's your main system, don't do it!
...just my 2 pennies...oh yeah!