No, it's not anything related to the browser -- I've tested this in IE8, Chrome 9.0.597.98, and Firefox 3.6.8 with the same results. The only way to get a populated list of your contacts (or GAL contacts) is to actually run a query. See the below images for what's actually seen and what you'd expect.
As it is right now:
What you'd expect to see immediately after clicking the To:, CC:, or BCC: buttons:
Any advice would be helpful if it's something I can fix and/or change -- or if I need to submit a enhancement request.