MAMEDC has been updated with the following news:

I rewrote the gfx engine so it uses the dreamcast TA chip and it looks really awesome switching over to the TA provides automatic stretch and anti-aliased gfxs! it even looks better than the bare mame on my pc+19″ monitor. i’ve even noticed that the new gfx code is a bit faster than before..
also, i’ve compiled the ghost’n goblins driver into mamedc and it works pretty well

some (badly taken) screenshots from the upcoming version here

Anything involving Ghosts ‘n Goblins on my DC is good news to me
keep up the good work Christophe!