-Rachel is in New York, and she's either an understudy or vocal coach to a performer she's watching on stage.
-Finn is a teacher in South Dakota, lying in bed with his cutely snoring wife and thinking about his two kids sleeping in the room down the hall.
-Kurt and Blaine live in London, Kurt has a tiny shop where he dreams up and sews his own fashion designs, Blaine is a professor, and they dance together to the radio.
-Mercedes has a recording contract and always wears Kurt's designs to red carpet events, but her vignette is actually a little sad.
It's possible that this may only be on ff.net, which I cannot navigate for the life of me, hence why I can't find it again.
Found! Dream a Little Dream Of Me: http://community.livejournal.com/kurt_blaine/81125.html