There’s a handy feature in the Filmstrip that gives you access to a wide range of info about your photos no matter where you are in Lightroom.
First you need to enable Show Image Info Tooltips in the Filmstrip. Just right-click (Ctrl-click) a photo in the Filmstrip and go to View Options and make sure Show Image Info Tooltips is checked. Once enabled, all you need to do is place your cursor over any photo in the Filmstrip to make the tooltip appear.
The information displayed is the same that is shown in the Info Overlay when you are in Loupe View, which means you can customize what you see in the tooltip. Pretty cool! This works the same in both Lightroom 1 and 2.