Even more useful would be to have it integrated into the sidebox (the one that contains chat, movelist, etc.) - just put it in another tab.
I definitely agree that one needs to be careful in using it. The best use I have made of it is in a themed tournament, where I could explore the particular opening we were using and see what kind of positions were most advantageous before starting my games. A great tool in that regard.
Many people don't use databases because it is not convenient to do so. Even Game Explorer is a bit of a chore to use. One of the suggestions on the Wishlist was closer integration between the standard board and Game Explorer. If there was a one-click button taking you straight into Game Explorer from the current position, imagine how its use would rocket.
Used as an Openings Database, Game Explorer has at least TWO distinct functions:
First, it lets you explore various games databases (Master Games; your own games; other players' games) to investigate how a game could be continued. Also, it provides (dangerously misleading!) percentages showing the number of games in the specified database with a particular continuation.
Secondly, it labels the opening sequence e.g.
1.d4 : A40 - Queen Pawn Opening
1.d4 e5 : A40 - Englund Gambit Complex
1.d4 e5 2.Nf3 : A40 - Englund Gambit: Declined, Reversed Alekhine
1.d4 e5 2.Nf3 e4 : A40 - Englund Gambit: Declined, Reversed Krebs
1.d4 e5 2.Nf3 e4 3.Ne5 : A40 - Englund Gambit: Declined, Reversed Mokele Mbembe
The second function would interesting as a commentary - even if it was not displayed until AFTER a move had been submitted.
Leaving aside, for a moment, the point that many people don't wish to use an Opening Database (in correspondence chess) - and perfectly reasonably, choose not to do so; it would be a great way of becoming more familiar with Opening nomenclature for those who wish to learn during game play.