I could tell you one thing. Apple purposely chosen the 7th for their conference. With Sprint's NYC/LA event, they need to find ways to "plug in" the EVO 4G. NYC is already primed for WiMax, and work already started in L.A., though I don't know how far along the work is yet. I say activate both, and have two major markets primed for 4G.
Having said that, LA event has nothing to do with the EVO. It's a film event, though the device will be shown here and there. No breaking news happening in this event. NYC is more of a EVO/Disney event, though I don't think you'll learn anything major. My invite already came through, so anything I learn from there, you guys will know (though I already know almost all that needs to know. Incredible release date and pricing was announced 2 weeks before launch, and this might be the same with the EVO. Marketing started weeks ago, so all they need now is TV coverage showing off some features that the phone will do best. Imagine setting up the EVO in your car. Your wife streaming Pandora in the front, and your two kids watching Monster vs Aliens in the back from their laptops. Dad seems lost so he decides to use Sprint Navigation, but his boss from back home decides to video call him. Wife and kids still doing what they are doing, regardless of the video call. That's the power of the EVO 4G with WiMax. Show this in a commercial, and watch the buzz explode.