I believe my friend and her team went down there last year. I don't know how she felt about it but to me it seemed like more of a "fun" tournament then one for actually playing softball. There's a lot of glitz and glamour and fancy things, but I'm pretty sure there were a very small amount of teams there. And there's no qualification needed, you just give them the cash and you're in.
Not my type of tournament, but if you're into that stuff then go for it.
I know a team that went this year. Their experience was the same as softballninja describes. It was a small tournament and the level of competition was not much of a challenge. But they had fun seeing Cooperstown.