I'm not sure why Cakewalk is hesitating on the VST3 bit - VST3 is supposed to be backwards compatible with VST2.4, and possibly even older versions. There is probably a pretty good reason, at least from their perspective.
I think this only underscores the need for open standards... while Steinberg has been pretty decent with both ASIO and VST, it has not always been smooth sailing, and it would be naive to expect it to be. Both of these pseudo-standards offer them some competitive advantage.
Given that the MI community embraced MIDI it does seem odd that they did not learn from that, and make VST and ASIO more open...