The thing they seem to neglect is that diffusion of nutrients is one of the dominant size limiting factors that constrains cell size. That, presumably, would change on Titan. If anything the cold should make diffusion slower, no? Still it's a cool idea, and I think that we should be exploring Titan, Europa and Enceladus for life ASAP.
> That means one day, it's possible — not likely, but scientifically plausible — that we will get to meet a life form in our solar system that's not a puny, dumb little thing, but a huge dumb thing. Like dog-sized. Or maybe Volkswagen-sized. So if a single cell in an environment like Titan is the size of a car, how large would a complex form of life be...?
I've noticed in more recent sci-fi comics I read (yeah, yeah, I know) that the idea of biological spacecraft is becoming more and more popular. It's probably because it gives the writers and artists another angle to play with, but I think it helps to push the public's imagination further into the realm of what might be possible. It is, for all intents and purposes, an infinite universe and by all accounts, it's very unlikely that any intelligent life we might encounter would resemble us closely, if at all. And considering the sheer diversity of lifeforms found on our own planet, it really presents us with this idea that alien life will not only be alien to our ecology, but to our imaginations as well.