QUOTE(jaguar @ Jun 3 2008, 09:09 AM)

I am a US citizen, my fiancee is a Canadian citizen. We intend to marry in the states as soon as possible. Should we file for a K1 visa or have her come to the states, marry quickly, and then apply for a K3. She wants to start working in the US as soon as possible. We both have college degrees.
You are going to have to decide which is most important -- being together quickly, or working in the US as soon as possible after the visa is issued.
If you want to be together quickly, file for K-1. It is tending to be processed in about 6 months or so (I could be wrong with my figures, you might want to do some timeline research on here for current times). However, like ZeeNusah said, it takes time to get work authorization, and if getting married in Canada is important to your fiance, you won't be able to do that with a K-1 and you will have to take into consideration as well.
If working ASAP a factor, get married and then file for the CR-1 spousal visa. This takes longer to process than the fiance visa but once it is done and your wife is in the US, she will get her 2 year green card and can work right away, thereby bypassing a lot of steps others have to take. The separation will be longer, but you can still visit each other while waiting.
K-3 spousal visas used to be processed quicker than CR-1s, but it no longer seems to be the case, and you aren't work authorized when you come to the US, so you'd have to wait for that.
Definitely check out the links to the guides that ZeeNusah provided in her post, read everything carefully here on VJ and on USCIS's website, ask questions if you have questions, and decide for yourselves what path will be the best for the two of you.