I just started noticing this too. The wifi symbol still appears, but it isn't connected. Toggling it off and on works, but it's a hassle. It usually happens after it's been idle for a while, I think.
This could be a router problem. The Droid X is finicky and some router firmware has been rewritten to accommodate it. Be sure your router has the latest firmware. If it does and the problem persists, use a router model known to play nice with the DX.



Yeah, I just noticed that after typing my last message...changed with Froyo. Separate for each... gmail, hotmail, messaging, etc. Testing now.