The release of the ST3 beta has shown exactly what this is about - it's mostly about money and nothing else.
Had it been about doing something for all those customers who thought they're paying for something which was going to receive bug fixes, we'd have received updates beyond the 2.01 update released last year.
The forums are filled with a lot of bugs and defects which are clearly not caused by the machines of the customers or by their software.
I really don't understand why things were done this way. It's a very sneaky way to handle things. Furthermore, since ST3 doesn't bring changes which are as important as the upgrade from ST to ST2, it looks a lot like a forced major version. It's pretty much what the big companies do with a lot of software suites - making a few bug fixes and slapping on a label with a new major version to get more money and to avoid offering any further support for the new version (oh, we're sorry, version 2012 isn't supported any more, buy the upgrade to version 2013).
Either way, giving access to current customers to the ST3 beta and not providing any further updates to ST2 is sending a really clear message: if you want bug fixes, always pay up for the latest version; otherwise you'll have to stick with what you've got.
I don't know what other people want, but I want STABLE software which actually receives updates. I don't give a rat's ass that ST3 is now using Python 3, there will always be a newer and better thing to use in any software project for any purpose. So that means it's OK to build a new ST, but bug fixes made for ST3 and future versions must also go into the stable ST.
I really hope people who don't own and haven't paid for ST already will really think about this before they pay for ST and before switching to it. At least that will save them from the frustration of seeing issues upon issues which don't get fixed.