double tap the homescreen at the page you want and the bar will go down.
This is a discussion on trick for expediting hiding of pages-bar when flipping through homescreens within the Droid X General Discussion forums, part of the Droid X Discussion category; double tap the homescreen at the page you want and the bar will go down....
double tap the homescreen at the page you want and the bar will go down.
or you could just hit menu when it comes up
Tapping anywhere on the screen that doesn't have a widget or shortcut also works.
Hitting menu means moving your thumbs considerably from their position. Its easier to tap the screen.
Or use another launcher (Launcher Pro, ADW, etc)