Was at Artichoke on 14th st the other day at 2AM and Umbrella was blasting through the speakers. The radio sure seems to think Umbrella is relevant to the pop music scene, so I vote "yes."
It is a classic song, yes. I'm not sure if it is "relevant", but that depends on your definition of the term! I don't hear it on the radio or anything, but "Umbrella" is typically one of the first things people associate with Rih. The song itself has aged very well and takes me back to 2007 as soon as I hear it. Same with Danity Kane's "Damaged".