First thoughts are that XNA Studio was totally painless to install and get up and running. The documentation is pretty good for startiung you off. What is needed are so great video tutorials to bring us up to speed on C# itself in the game environment.
Same here. So far the experience has been painless.
I guess it all depends on where things go over the next year or so. M$ has been none to make trends, and hold other to them (wether we want to or not). In some cases they fail, in others, they create a new 'standard' (loose term).
I really don't want to spend an amazing amount of time developing my own 3d engine (I am just one guy), or purchase someone else's when they might choose to drop support for it.
XNA seems like a doable future for me (and for my employeer), as it looks like the future of not only 'quick and powerfull windows game development' but also 360 development (regardless of if you need a xna member ship to play the output now, things can always change).
Besides, creating games that the 360 lacks (genres) in at the moment is like shooting fish in a barrel. Being on that up-swing will be someone worth it.
Other consoles:
PS3: pssshhhh, I dont put much stock in it. It's costly, bloated, over-hyped. And Sony is known for screwing the little guy
Wii: nice toy, fun to play with, but not the best looking for indies. The gfx dont rival a pc, and it still gets mixed reviews (not to mention it's still not in stock anywhere).
Overall, the 360/Windows marriage for game creation looks like the best one as it hits 2 potential markets. Where it opens in the future is up to M$, and I am sure with enough money or enough bitching they could open it up even more to cater to us indies. We just need a loud enough voice (or a big enough wallet).
This is what my employeer wants more than anything.