Blade3D was just released a few weeks ago.
A slick IDE for XNA, we've been using this engine for the last year or so, and in even in prerelease form, was a solid engine. We could give it to the art and design guys, and they could see their work in real-time, as it's mostly a WYSIWYG interface, at the same time not limiting the programmers ability to code.
The devs are all top notch and their pricing plan is on a month to month basis ($14.99 for the casual developer, lifetime 15% off if you get a subscription before end of the year) rather than sinking a ton of cash from the get-go. All throughout beta, the developers at Digini were answering our emails and IMs, helping us use their engine, and they really wanted to make a badass interface.
I sound like a total shill right now, but whatever. This is a sick next-gen engine, easy to use for a guy who knows some code and can make models to crank out a prototype in a week, and robust enough to support a full game.
