I disagree. 4 sounds good. Especially if one of those is twice the price and twice the size of something like Point Lookout, which is more of a possibility with 4 DLCs. And to me, Fallout 3... well... Mothership Zeta just doesn't count. So it is about the same for me.
I absolutely love that idea.
I tried to start a thread about the "kinds of DLC" people wanted to see, if they wanted it to follow the Oblivion model (house packs, minor quests with reward items) the Fallout 3 model (minor expansions, a new location + a new mechanic + a handful of new items, perks and rewards), or the Marrowind model (full-on x-packs).
I would love to see something the size and scope of Oblivion's Shimmering Isles for FO:NV, in addition to the 4 stated expansions. And maybe a few new "house and a 20-min quest" type mods (like Frostcraig spire for instance)