That's gotta be 3/4 of their client base right now, I don't know anyone who has one that isn't a "work" phone.
The LED is a DAMN good feature. I don't think its overappreciated at all. Throw on BerryBuzz, and you can get custom LED color alerts...so when a text comes in, blue light, e-mail red, call green, etc.
The lack of a notification light on the iPhone is the #2 reason (after lacking a decent notification system) that I haven't touched an iPhone since the 3G.