I really don't pay enough attention to stand up comedy to have an up-to-date opinion on it, but what the heck, it's a slow snow day, so...
I was a huge George Carlin fan in the very early 1970s...then he got a bit too predictable in the early 1980s so I stopped liking him...and then he got wonderfully un-comedic, more like a philosopher/political commentator/poet in the early 1990s, so I became a huge fan again.
Nearly every routine I've heard by Billy Connoly, Steven Wright, and Margaret Cho has had me absolutely roaring in hysterical unstoppable laughter for 10, 15 minutes at a time...though, with maybe one exception (Cho's "Ass Master" routine) I can't remember a single joke 24 hours later.
Conversely, there are a few lines from routines by Jake Johannsen and Elaine Boosler that I heard once 20+ years ago that I can still recite verbatim.