I find Jinn's link interesting, because there's a piece on cosleeping in my infant/child development textbook that suggests that cosleeping might actually be beneficial in preventing SIDS; this is apparently due to the fact that in cultures where cosleeping is common, SIDS is rare (McKenna, 2002, McKenna and McDade, 2005:
Elsevier). There are a number of studies out there that directly contradict the information presented in Jinn's link--that's science for you, I suppose.
So here's some information on SIDS taken from the same text (Berk, 2008): SIDS is the leading cause of infant mortality for children under 1 year of age. Its incidence peaks between 2 and 4 months. There is no precise known cause of SIDS. Some associated factors with SIDS: prematurity, low birth weight, poor Apgar scores, limp muscle tone, abnormal heart rate, abnormal respiration, disturbances in sleep-wake cycles, and a mild respiratory infection. There are several hypotheses as to the cause of SIDS: these infants have problems in brain function that prevent them from knowing when their survival is threatened, environmental factors such as maternal cigarette smoking or the baby being overly warm, and again, respiratory infections.
Personally, I'd like my child to be able to self-soothe, but I also understand how important it is for an infant to attach securely to its parent, and being able to comfort an infant quickly definitely helps build trust between infant/parent, leading to that secure attachment. I would probably go the bassinet-by-the-bed route, because I would like them to be close but not in bed with me. I like the strategy of moving the bassinet further away the older the child is, until the child is in their own crib and soothing themselves at night, as that is appropriate when they are older. As a childcare worker, I appreciate kids who can self-soothe at nap time.