I've not dabbled yet, but looking at the videos I agree with the consensus... the Smallthought team has put together a nice, simple system in a short amount of time via Smalltalk and Seaside.
This blows Ruby on Rails a bit out of the water. Maybe it will inspire RoR and other systems to become even more radically simple.
The Dabble design has borrowed a number of good ideas from OVAL and Lotus Agenda. They've also thrown some other good ideas into the mix. The mix looks good, great even. Because they've built on what I consider some under-explored fundamentals (simple mechanism to combine semi-structured information) and the simpler interactivity enabled by Seaside, Dabble could continue to go a long way for some time. This kind of thing, if not Dabble per se, should be a fundamental building block of those office applications you wish you had but would cost too much to develop.
The exciting thing is there are even more good ideas that have not been incorporated. I guess the unexciting thing for the developer community is that Dabble appears to be a commercial venture. But I guess that's good for them, because they have a winner on their hands.
I think it will be easier to dabble than it is to jot.