DL 2.1 issue with Exposé when performing iPhone sync

When the library is being synced with the iPhone app and the HUD-like sheet is visible displaying the sync status, switch away from Library to another application. Using the "Show All Windows" Exposé effect, switch back to Library and the HUD sheet will not be visible, or the Library window will not come to the foreground at all (the behavior is not consistent). Clicking on the Dock icon for Library will bring the application (and the sheet) properly back to the foreground.