Honestly, I started out from AC2 and didn't bother playing AC1. You really don't miss out much story wise in my opinion, and if you need to read up on it, there's always the AC Wiki.
Also, while it would be bad if Mario games were spit out every year, when you look at it...they do. There are different renditions of Mario. Mario Party. Mario Tennis. Sonic vs Mario at the Olympics. Paper Mario. New Super Mario Bros.
The other main Nintendo franchises don't do that (Zelda and Metroid), but I think you get the idea about Nintendo milking Mario.
Never been a fan of companies spitting out a new rendition with very little changes every year. Like hell I would pay 60 bucks for a game that has subtle changes. AC Revelations will probably be a rent for me just like Brotherhood. Smart move from a business end, but stupid on us buyers.
DLC stuff is stupid too. Especially when it's already coded on the disc.
/endrant