That's great, kristilew. We loved the TB Danube cruise and it sold us on riverboat cruising. I almost booked another cruise with Tauck for next year, but finally decided to give Uniworld a try. I hope your guides and cruise director are as good as the ones we had. They came up with some great extra activities for the kids (and some that included the adults, as well) that aren't listed in the itinerary. The itinerary is the same as when we took the trip, except they've replaced the white water rafting, with a knight tournament and medieval games. I know they got a lot of negative feedback on the rafting and they dropped it the next year, so the change is good thing. It was on a short man-made training course and involved a lot of lugging the heavy raft back to the start of the run. Everything else about the trip was fantastic. Before the trip, I wasn't particularly excited about the dinner at the palace in Vienna, but it turned out to be a highlight of the trip. I hope you enjoy the cruise as much as we did.
I was going to say what you did: not much more than on the website and still doesn't explain much of the logistics. The only new "info" is in the two above, but it's not detailed enough to make a judgment. My suspicion is that they don't know themselves and don't want to box themselves into anything (i.e. the "approximately 40 people"). It still seems like they are assuming that groups will naturally form into even numbers for the excursions, which doesn't seem very realistic. Groups "may be staggered" also worries me--does that mean we are sitting around waiting until its our turn? (I'm having visions of sitting in the Walt Disney theater with my big Port Adventure impatiently waiting to go, LOL). 
