i would probbaly havta say yondermountain string band. I love railroad earth but they dont have many songs out yet so it can get repeditive. Alot of people consider SCI bluegrass. Their older Bluegrass jams rocked but now they get so psychedelic then yell out hoe down i just get confused. its all good fun.
I'm not that familiar with many bluegrass bands, but I LOVE the music. My favorite singer is Gillian Welch, I don't know if you'd consider that bluegrass or not.
im not to familiar eaither. i hear jgarcie and grimson were an awsome mix but i havn't been able to get any of there stuff.
wow, this sounds like a new grass thread (GW is a singer songwriter, I 'd call her Americana) so my answers are yonder, Sam Bush, Railroad Earth, Moonshine Still, Jerry Douglas, Tony Furtado(although he's going rock thaes days, his Ten Brooks and molly is exquisite) Heartwood Hollow many more. Cheese is not newgrass anymore.