i know the dreamcast is the love child of many people on here, but it seems to me that its more hassle than its worth. why dont you just wait until someone releases a decent way to interface the dc (or wait until the emulator WIP works better) to the cab....otherwise...just build a cp for your tv and hook your dreamcast up to that. id LOVE to put a dreamcast in my cab to play cool games like crazy taxi, fighter games, and blitz...but its just to inconvenient to have to change discs every friggin time you want to play a game. am i the only one here? please dont hate on me dc fanboys because i dont share the joy of having to open my coin door every time i want to change a game though 
I've been playing my Dreamcast inside a cabinet since January of 2000, and never thought of switching games (or switching over to PC/Mame) to be a problem or hassel. I think this issue of it being a pain arose from those people who have started out playing mame, and switch games like every 5 minutes because those old games get boring really fast. When you have 1000 some odd games at your fingertips, you can't help but switch games quite often.
On my Dreamcast, I find myself switching games maybe once or twice a day at most. And how much of a pain is it to open the coin door and hit eject? As for switching back and forth to Mame/PC, I do that much less often (being the dreamcast has better games

), but I just pop the control panel top, and switch around my molex connectors and video cable and I'm done.
Saying this is a pain to do, or waiting for a DC emulator with acceptable framerates and supported game list is just plain lazy. These people just don't want to put any more work into their cabs.