Sycraft
There we go. Have to say it is a little worrying just because I figured CW was counting on renewals as their recurring revenue stream. If they are letting you buy out of that I worry as to what their long term funding plan is. Hopefully not to sell out to Facebook like Occulus :D.
I think this is an experimental adjustment to the business model. This will give them an injection of cash, that they wouldn't otherwise get in the short term, from their existing user base (us). This will presumably keep them solvent while they release some more industry-leading stuff that will, if all goes well, bring lots more users into the fold in the future, which will offset the revenue they won't be getting from us 'lifers' in the years to come (though I'm sure they'll release other things for us to buy, and we will likely buy them...)
It's an act of faith on our part, investing in their future success where, hopefully, everybody wins in the long term. That's my read anyway.
EDIT - it's an act of faith on CW's part too, it should be said! And the fact that they're doing it leads me to think they have a fairly good reason for being confident. Otherwise why take the risk of foregoing almost-guaranteed future income from those of us who have updated reliably for years and are therefore likely to continue doing so?