I'm thinking that in fact how you feel about Santa is a good indication of what you, personally, should do. If you think its lovely and magical, etc., then your children are likely to be like you - through genetics and/or a similar environment - and thus also really enjoy the actual belief in Santa. But if you're wary of the idea and have memories of being distressed at the deception, then similarly your children may have the same response, and thus doing the lighter-touch stepping back and letting them absorb it from the environment only, or reassuring them no stranger is really coming into their house at night, is likely the best way to go.
I'm like the latter - I 'found out' age 4, and honestly didn't realise that people kept the belief much longer. I found the whole thing uncomfortable as a child and a bit creepy. People have mentioned ASD traits and kids being distressed by Santa, and both DH and I have such traits (although neither diagnosed, but by golly, I'd be totally unsurprised if DH was easily diagnosed if he asked about it...) and as I understand they think it's genetic, DD could as well. Being extremely concerned about placing things into 'real' and 'pretend' boxes as a way to organise her world appears important to her. It strikes me as a poor idea to run roughshod over that for something that made me uncomfortable as a child.
But I can imagine that the people on this thread who are horrified at the idea of no Santa, then obviously did not find it distressing as a child. Their kids will have a high likelihood of finding it magical and lovely.
And finally, the parents current attitude has an effect. If I find it a bit weird and uncomfortable, if I "did Santa" no matter how much I try to make it magical, my child will probably get a sense of my distress off me. Alternately, if someone who absolutely loves Santa decided to not do it through social pressure or something, and then was understandably sad and missing it, their kids would probably get a sense of a downer around the season off of them.
So, in all, I think it's best to be guided by your attitude.