For me sketch comedy has not been done well since The Kids in the Hall went off the air in 1993!
BUT....there does seem to be a new comedy troupe that seems to have a lot of potential.
They are called
The Whitest Kids U Know
While they are a little rough around the edges with some skits going nowhere and a few that are too long and annoying.....I'd say for every 1 crappy sketch you have 3 good ones....overall they are damn funny. They were on a station called FUSE.....which I know nothing about...but have now moved to IFC for their second season, which will allow for even more crude humor since they are not censored. You can see a LOT of KITH influence in this group.
Here is what was IMHO the funniest skit of the first season....it's called "Slow Jerk"......ENJOY!
http://www.youtube.com/watch?v=BkgMbU-we1o