Wait, wait! So let me get this straight there are 4 Factions in FNV: NCR, CL, Mr. House and Vs. Mr.House. Unbelievable! (sarcasm)
So if these are the 4 confirmed and no more, why carry on about "The People of New Vegas" being a faction...
Because it's unclear what Mr. House's "faction" is going to be. I personally think he wants to benefit his industry but not the wasteland, and against him is to essentially bring down New Vegas by giving everyone in the wasteland power, but I can't confirm this, only speculate.
That's the only real reason to continue on about the whole "people of New Vegas" thing, as we're unsure what it clearly means by "New Vegas" (the city, or the entire wasteland).