I grew up with the space program. Mercury, Gemini, Apollo, the lunar landing and everything associated with it form a huge part of my childhood memories. Thus the Moon holds a lot of romance and nostalgia for me.
I'm torn on the Constellation project. Obama has canceled it, the Apollo astronauts are excoriating him for it. I'm not enough of an expert to know whether a return to the Moon is really worthwhile or not. I can see how setting up a lunar colony, with an observatory and scientific station and what-all would be scientifically and technologically valuable. Long term habitation of the Moon would be a proving ground for technologies that would be useful for flights to Mars and elsewhere. The technological prowess that would develop from having regular flights to and from the Moon would be impressive.
The downside is that in a lot of ways, the Moon is a dead end. It's not useful as a launching platform for missions elsewhere. There really isn't that much more science to be gained from the surface of the Moon itself that couldn't be gotten in Earth orbit. Rockets to go to the Moon and back wouldn't be powerful enough for interplanetary voyages, and crew protection needs would be completely different. An entirely new class of launch vehicles would have to be developed anyway, as lunar technology wouldn't be all that different from Apollo - and we've already been there and done that. You can make a pretty good case that however romantic and impressive a new lunar program might be, it's not really a good use of scarce capital.
My own feelings are that the incremental approach of NASA back in the '60s was the right one. Let's master trans-lunar flight, then build on that technology for a trip to Mars. We needed to invent a new booster to get to the Moon in the first place with the Saturn project, but we still used other stuff for Mercury and Gemini as we figured the rest of it out. The Constellation technology could gradually be upgraded with better and better stuff, as well as a testing platform for Mars caliber designs. As a starry-eyed layman, than seems to make sense to me. But I'm a starry-eyed layman, so what do I know?
Anyway, I'm taking a wait-and-see attitude toward the whole space exploration issue at the moment. What I want more than anything else is to see some commitment to do something with manned space exploration. It's something that we as a culture need to do. We need goals. We need audacity. We need technological challenges to keep us from getting bored and complacent. NASA is a hugely important part of our cultural legacy, something that helps to define who Americans are. The Shuttle program was largely a waste of time and opportunity, a dead end technology in its own right. I hope President Obama can reignite that noble cause I knew as a child.