Well, good thing we have 40+ hours of single-player.
If it does happen, then blame Ubisoft for not releasing a public demo/beta and for going in a EA or Activision route. "You can only play the beta if you boost pre-orders for a certain game that we know that you will not like, or play."
Like most people who have been anticipating this game for years, single-player is my number one focus. Multiplayer is certainly nice and enjoyable, but I think most people's experience from the series is that they'll at least dive into single-player for a few hours before playing multiplayer.
Battlefield 3 and Bad Company 2 had these issues. Hell Battlefield 1943 severs were down for 24 hours on release. Its likely it will happen here, as almost all games that rely on servers seem to fail their projections for server load on release.
I do wonder though, are Ubisoft games Player To Player or server hosted? I know they rely on servers for something, but are they still P2P?