Achtung, achtung, the spoiler alarm is still ringing!
As a side bonus: I'll start building again soonish, though it depends heavily on the weather (on a clear day it's so much nicer to paint on the balcony), but soon I'll stop talking about Vegas. At least I'll stop doing that here for a while :P
When I got my new task from Caesar (kill House, come back), I also talked a bit with Vulpes Inculta and the leader of the Praetorian Guard. Got some minor tasks, completed them promptly to gain some fame, marched back to Benny's suite to chat with Yes Man as the Wild Card -series of quests suggested.
At this point I had a good bunch of open quests, around ten of them. All except one (Red Lucy wanted some Giant Mantis eggs) were somehow related to the ending. I had already decided to see how this "sultan instead of the sultan" solution would play out, which meant working on the Wild Card quests.
The first task was to get rid of Mr. House somehow. After fooling around with a couple of terminals in Lucky 38 I ended up in some kind of a super secret place. There was a long catwalk in some kind of a weird hideout, somewhere deep underground. In the end another terminal and apparently a capsule or something. The hell was this? So, some hackzoring ensued! But no, none of that. It just opened, what kind of a quest was this supposed to be?
Oh well, open the stasis chamber, yeah yeah, I don't mind about any contamina... errr... who's exactly going to be contaminated? Me? Bah, let's do this already.
Hey, it's semi-mummified House! Mein goth... I even forgot to take a screenshot of it, I was so confused by the frail old man connected to the machine and the network. He was complaining about how all his plans and decades of preparation were ruined and why did I do that and blah blah blah. Off with his head, I shot him in the face with a minigun. Then I observed a huge amount of "quest added - BLA", "quest failed - BLA" and I almost got scared if I ruined the whole game. I'll comment on that in a moment.
In the end I had two tasks left. The first one said "go back to Yes Man" and the other one was still the same Red Lucy's quest.
So I marched back to Yes Man and he was as excited as always and wanted to go to Mr. House's termina. Ok, I walked there yet again with the robot. After a bit of in-game rebooting and updating of the rest of the Securitrons Yes Man gave a couple of more quests. Some of them I had already completed during my adventures. I had to go back to the power station that I mentioned the last time, though this time no one got angry when I just marched into the control room, flicked the switch to route more power to my robot army and left.
After that all I had left was to go to the Hoover Dam (the game at least asked if I knew what I was doing), flick another switch in the generator room (one of them) to get even more power for my robots and then kill all the Legion troops on the outside. While I was outside, I was sent to the infamous Legates' camp where I got to finally chat with him. Of course I hadn't thought of reading a "Meeting People" magazine to boost my Speech to 100 so I failed one of the many speech checks and the Legate decided that the time for talking was over. After a brief-ish struggle I killed him (and his face wasn't ruined! I felt cheated).
When I walked back towards the Dam a gate was blown up and a happy general who I hadn't even heard of before came in with his entourage of gas masked soldiers. He was happy until I had finished talking to him: I made sure that I was the boss and I had won. He didn't take it too well and got aggressive. Me and my small team, backed up by an army of Securitrons did a short job of them. Muah.
To finish the last task I just walked to talk to the Yes Man. He rambled a bit about what's going to happen and how he's going to update himself and that was it.
Now about those "Quest X added", "Quest X failed"-things that occurred right after Mr. House passed away. Apparently until that point the end is still completely open. You can take it however you want, but that is the one that decides how the game will end. I had all four ways open: the Independent Vegas I got, House's Vegas, Legion ending and the NCR ending. When you take the deciding step towards a certain end, the rest of the quests will automatically fail and you can't get more from those factions.
Because of the end I went for, I didn't really get to receive the big no-quests like "Don't step on the Bear" or its Legion counterpart (can't remember the name now, sorry). Those descriptions both say that if you keep working against their interests, they'll stop giving you more quests. Ok. I just got them and they failed immediately because of how that part of the story goes, I couldn't "redeem" myself in their eyes. That also meant that I skipped a potentially big part of the story. Or not. That's the story I got this time. I just couldn't play all the factions against each other until the very end and only then decide who to go with just for the Final Quest. Cool, now that I figured it out.
Anyway, after the ending I just loaded an older save and kept going on from that. This time I went with Mr. House instead and see how his autocratic New Vegas would turn out. After that I'll go for the Legion's side and only last I'll bother with the NCR jerks.
At this point, after taking quests from "the House Always Wins, I" to "the House Always Wins, V" I've got more backstory and explanations. Of course it's because Mr. House is still alive to be able to tell me these things, Yes Man was a robot and couldn't tell me anything he couldn't read from the Platinum Chip. Now I'm supposed to get rid of the BoS people in the Hidden Valley and I dislike that a bit. But a job is a job and I'll get it done - a bit later. Because the quest didn't interest me at this point that much I decided to go to see what I had missed on the map so far. There's plenty of awfulness to be seen and killed.
One of the more awesome things I've already found is this NCR Ranger helmet:
By the way, I thought this was going to be a quick, short post over a couple of paragraphs only. Apparently I was wrong yet again.