I'm iffy on waiting for this. I'm eligible for an upgrade whenever I make my mind up. :P
Like a lot of others in this thread, that 4 inch screen really is the sweet spot for phone size. On the other hand, I don't think an Incredible 3 would really be a huge improvement over a Rezound. It won't be quad-core and LTE, because as I understand it, the Tegra 3 isn't compatible with LTE. It'll have a nicer camera, but the Rezound has a very nice camera, anyway. And Sense 4.0 is a moot point, since that'll get ported.