Yes, you definitely want it. I finished it about six times and had great amount of fun. It was one of the best RPG's released since great titles like NwN, BG and PsT. Must have if you don't have it yet.
Just a note that this does NOT include the many, many DLCs the game got. Like with some drug dealers the first taste is free while further hits will cost you.

True, though game without DLC's is really good enough. Yes, I know, temptation impossible to resist... *sigh*
Steam often has it on sale with ALL DLC for like $6. Origin is also a garbage platform, as anyone who has actually used Origin will tell you.
DAO spawned Nikolai (to all of your pain) and led me tons of great fun. However, the "origins" don't really matter.
Also it's the same plot as Mass Effect 2.
Also the game never game me the achievement for romancing Liliana, which is obviously the gravest transgression it could have committed and supersedes all other slights against me.
I thought it was a great game, played it through about six different times, became a fan of it. Saw that Dragon Age 2 was announced and I'm like "YEAH! Bring it on!", then Anders molested me...

._.
Anders was a disaster in DA2 for me, comparable only to Fenris. Shame, because I really enjoyed Anders when I played Awakening.