Does the length of your domain registration have any impact on the SERPs?? According to a Google document the answer is (potentially) Yes!? Most people register a domain for 1 year.? This helps keep cash in your pocket, it also saves you money if you factor the present value of money (i.e.? paying for 10 years of registration for a domain today costs you more then paying 1 year at a time for 10 years).? But if you have a domain that you are developing you may want to bite the bullet and buy the maximum length of the registration allowed.
Paying $100-150 up front for a 10 year registration is worth it (to me) for my developed sites if there is a potential chance that by doing so I’ll get some help in the SERPs.? We all know how important it is to move up just one place on the first page of a search result in Google so I would consider this money well spent if there is any impact.? (if you don’t know how important moving up a spot is, here is a Google first page click distribution study done by Cornell University)
So if you have a domain that you developed and you can afford maxing out the registration period you may want to consider doing so.