I've always considered Greyhawk to be the most generic campaign setting. I don't mean that as a slam - I think that was it's purpose.
But, as a result, I don't think there's much "gee whiz" about Greyhawk - it's just *there*.
For years, I never had a campaign setting, per se. I ran a lot of Planescape, and Al-Qadim and played in quite a bit of Dark Sun - so those were our campaign settings.
When I a ran a "generic" game, I ran with the Forgotten Realms maps and gods. I didn't stick to canon much (no one cared), and it seemed a far more interesting, and more importantly - far more detailed place than Greyhawk was.
Nowadays, I use the Wilderlands. It's arguably as "generic" as Greyhawk is, but it's FAR FAR FAR more detailed.