what happened to 5.0?
Are they doing 6.0 and 5.0 in parallel?
It must be a parallel project.
When 4.0 was released to the public, the next update provided 40 b13 nightly users was a 4.2 alpha. (some plug-ins break)
They are moving to a Google Chrome like development schedule. So yes, basically, 4.0 is stable, 5.0 would be beta, and 6.0 would be alpha. Soon, 5.0 will be stable, 6.0 would be beta, and 7.0 would be alpha.
They're really speeding up their release schedule. Not really related to the topic, but I'm curious why is the Mac build twice the size of the Windows one?
I wonder if they still package both PPC and Intel binaries together. This is usually the reason why OS X apps seem to be larger than their Windows counterparts.
I think the Mac version is a 32/64 bit universal binary. That might be an explanation, anyway.