I would go with Halo series because not only did it have an epic single player but it also one of the best online games ever!

While Halo introduced many concepts that have become FPS standard, MGS was the genesis of a genre. So 1 point for MGS right there. However, it's hard to deny the infulence of Halo on subsequent FPS games, a genre which far outpaces the stealth genre in terms of the sheer amount of games made. Tough to call...I seriously am going to sit on the fence on this one.

I would say MGS4.
Ive seen many more games take on the ideals of MGS series then Halo. Many developers might want the SALES of Halo but not the idea of it.

Assassin's Creed: one of the first games of this gen and I feel a very strong sense of MGS while playing it. The story and execution wreaks of Hideo Kojima.

Resident Evil 5:SPOILERS!!!!!!!!!! OMG this game is a blatent rip off of MGS4. If you have played both of these games you will see the startling similarity between Wesker and Vamp from MGS4. I mean you even had to take Wesker's "imortality" from him with the "syringe" from MGS4. And dont get me started on Jill. She may have stolen Nina Williams outfit from Tekken, but she completely stole Raiden's moves and style of fighting. The game also felt very action intense as well as boss centered like MGS4.

END SPOILER!!!!!!!!!!

the list goes on of games that finally take a deep story seriously in the medium just like MGS.

God bless Hideo Kojima...

Halo set the pattern for how to do FPS on consoles. Metal Gear was just a series heralded as brilliant. It, however, hasn't set a template for stealth titles alone. People don't talk about Metal Gear Solid killers, but they say Halo killers. A major reason probably is that FPS is far more of a popular genre than stealth. One could say the movie-like feel of MGS is influential, but LONG LONG LONG cutscenes are NOT the norm.

One can argue Grand Theft Auto is also more influential than MGS. Now, is MGS influential? Yes it is, but not nearly as much as other games.

That's a tough one. In terms of overall gameplay I'd have to go with Halo. In terms of storyline and character development- MG wins easily.

Honestly, guys, Splinter Cell and Thief hav had a lot more influence on the stealth genre, even on consoles.

You can argue which is better all you want, but Metal Gear isn't in the running, here.

halo. i see more games with online play than games being bad movies

I would say Thief and Metal Gear helped to put stealth on the map.  Spliter Cell can be said to be inspired by Metal Gear and refine it.

neither.

halo what did was get features from other fps and put it together its nothing revolutionary.

Co op? contra.

multiplayer split screen ? golden eye.

and this like deathmatch team deathmatch and other modes were in fps for ages.
and until halo 2 halo was also on PC.

msg neither since we have tps before, but tps got a better story than the average tps.

It's called Forge.

Halo3 didn't become what it was because of co-op/splitscreen. It was just icing on the cake. Let's also not forget that it has online splitscreen - it's a pretty rare feature in games today.