Hey guys.  Spoilers incomming! 
 
 
 
I've been helping NCR along all the way, I'm not up to a mission where the President is gonna come visit. But I've started wondering if I should side with Yes man instead, having allready killed Mr. House and Caesar. The reason is, I read on the forum that he's (Yes Man) more interesting the lots of the other factions, and heard Ryan talk about how he liked the character. But I don't want to feel like I'll just ruin all I build up so far. Would it make sense changing to Yes Man at this point? 
 
Thanks!

Beat it with NCR, but keep a save from right before then, and then go back and do Yes Man. That's what I did, shouldn't take too long.  
 
I found the Yes Man ending a little lacking, because it doesn't end how I thought it would, which made me a little angry. 

Ok, think i'll do that!

Yeah, because while you can alienate the other factions, aside from killing him, I'm pretty sure there's nothing you can do to alienate Yes Man. And the game is very specific about when you get to the point of no return (it's when you go to turn in the saving the president quest), so no worries about that. 

I picked Legion and I seriously regret it.

You can easily string along Yes Man, House, and NCR in a single play and be about 2 and a half hours from all 3 endings on a single save. Jeff didn't know what he was doing.

Does anyone know when the point of no return is regarding which faction to align with?  I've been hesitant to start the Caesar quest or some of the later NCR quests in fear of alienating the other factions.  I want to get the 3 possible endings in one playthrough.  After playing Dead Money I have no desire to complete multiple playthroughs.  Was anyone else horribly disappointed with Dead Money?

" I picked Legion and I seriously regret it. "

I just saved at the point where I had done all possible story missions except where I had to kill someone and then did all four in about two hours. 
 

I strung Caesar and the NCR along as long as possible but was always gonna go Yes Man.  The ending was mostly just watching the upgraded robots / Bomber / Brotherhood / Enclave kicking ass.

I wish you can give everyone the finger and walk away. 
 
That's certainly what I did in Vampire: The Masquerade. 
 
It was refreshing to tell all the factions to fuck off. I think that was the best ending possible (for me).

I want to side with Yes man but I sorta already blew up the robot army. This means I'll have to rule New Vegas with about 24 upgraded securitrons. Yes Man is optimistic about it at least, said thousands of securitrons would be confusing anyways, still not comforted....

The game spells it out for you. If you're helping one side too much, they literally create a new quest saying "___ knows you're helping ____, help ____ again and ____ will stop helping you." Couldn't be any easier. Everyone wants the Brotherhood dead, everyone basically wants the same thing up until the president mission. 

I ended up doing the NCR and finished the game. Have to say I'm not too impressed, but I think it goes back to the actual game mechanics, so not much hope there. I talked the dude out of it, instead of killing him, having already killed Caesar earlier.  
 
I'm really curious about what happens if you side with either Yes Man or Mr. House though? Do you gain access to the Vault behind Yes Man at some point?