I hope I'm not wrong here cause this would be really cool.
Nintendo has updated their GBA section to include new shots of Mario Advance, F-Zero, Napoleon, and Golden Sun. Click the names to see the pics.
What really grabbed me was this screen shot.

This is obviously some sort of menu selection screen. What I believe this is stating is that not only is one old school Mario game is built into Mario Advance...but 2! The original Mario Bros., and the ORIGINAL SUPER MARIO BROS.! Could it be? I think so.
Why would this be the first time we have heard of this? Because Super Mario DX is still available for the GBC. I hope that the original Super Mario Bros. is available even though I own DX. That wide screen will do the game justice. And hell, a 32 meg GBA cart should be plenty of space to hold all of those games. Bring it.