You do realize that 2.0 has only been public since October 26th 2009, that was less then 3 months ago. Cellphones are extremely complicated devices which require many many hours of engineering, development, testing and then finally manufacturing. During this time the manufacture has to also iron out contracts with carriers, suppliers, marketers and distributors. Most phones you see coming out now with 1.5 probably already made it past the R&D phase or were very close to being finished products. Sure they could have put everything on hold for 2.0, but then what almost be finished and put everything on hold again for 2.1? By doing that they would be sinking more money into a project that they really don't have a clue if they will get any ROI on. It's much easier and smarter for the company to release the product and then start updating it. Also remember that most of these phones require some sort of customization either manufacture or carrier wise - thats extra time too. Remember that 1.6 was only an quick release intended for very specific phones.
