There are probably one of two reasons. One is no biggy, the other is rather problematic.
The easy one is that Verizon may not have gotten around to sending out the automatic update to your phone yet. I agree it is unlikely, but possible. To resolve this on your own, pull up Settings, About Phone, System Update and it SHOULD tell you it is available and let you start the download. It will take awhile, so don't do it while you need it as a PHONE.
That leads us to what you need to do if you are constantly getting messages when you try that like, "Update server is not available, try again later" (not exact text, but close). If so, for whatever reason, you have a messed up set of software and a Factory Data Reset will be needed before your phone will be able to see the update.
I have posted very brief instructions about this on this post in this thread:
http://forum.androidcentral.com/mot...roid-x-froyo-update-thread-13.html#post374928
I hope this resolves your problem. It did resolve mine.
Personally, I suspect that some app I had loaded caused this "malfunction", but I have no idea which one or if that was truly the problem.
Good luck!
Scott