When I first tries delicious (yes, before the yahoo acquisition), stumbleupon, and digg, i thought that google should have a similar service to all of these. Stumbleupon was really fun to use but the classification of websites and setting interests was extremely messy but overall these services would be really cool to combine into one googley goodness.

does this seem like the type of thing google would want to eventually get into?

I think Google can reproduce the technology used at Digg, so the only real value is the community. (Same was true for YouTube.)