I'm working on a game called Lentilwars for a year now(i'm heck lazy).
I use FPC for it lazarus as an editor. I use SDL and my own net code + I just finished the 1st part of a Game Abstraction Layer for the blitter so I can swap between SDL and openGL. I think fpc is good for games programming specialy because it's so cross-platform(unlike even C which has "issues").

As for those unfinished parts of FPC, apart from the DLL (for big multi-language projects) I don't see any problems.
FPC also supports a few things which delphi doesn't have that might come in handy.