Is there a difference between a scientific blog and scientific journal?

In my blogroll, I link to Tim Gowers’ blog. He is a very eminent mathematician, and so it is interesting to see what motivates him to write a blog about mathematics. This latest post goes a large way to explaining why. He starts by speculating about the features of some piece of research that might render it conventionally unpublishable, highlighting two reasons; (1) it is not original and (2) it does not lead anywhere conclusive. He then goes on to show how either outcome might nevertheless be useful to someone, even if unpublishable conventionally. The rest of his post then concentrates on the cap-set problem in pure mathematics. It boils down to the observation that the community as a whole might often spot something that individual might have a blind spot for. Or, that others may in turn be inspired by lines of research which had apparently led nowhere for the original poster. Tim of course is favoured by having often 80+ comments appended to each of his posts!

I could not help but reflect that the culture of chemistry is rather different. The primary chemical literature is probably full of research that is neither original nor conclusive! Certainly, I suspect that few researchers would abandon the scientific journal in favour of a blog to communicate that unoriginal/inconclusive result. Am I in fact digging a hole for myself by implying this blog is full of such stuff? I do hope not! Take for example this post, in which I tried to establish what I (perhaps mistakenly) thought was an unremarked-upon connection between molecular biology and chemistry, namely that the left and right handed forms of DNA bear a diastereomeric rather than an enantiomeric relationship to each other. Or that the reasons given 57 years ago for the prevalence of the right handed form may not withstand scrutiny using more modern tools (this would not be the case in mathematics, where a proven theorem remains proven, even with modern knowledge). Or perhaps, that the overall shape of the double helix (and its further folding into a superhelix) might depend on the finely tuned properties of just one single bond in the molecule.

One might also remark that one does not always have to decide between a  journal or a blog; it is possible to do both (and stay within the rules). A blog may allow some measure of open review before the ideas firm up in a manner more suitable for a journal. This journal article for example owes its genesis to the threads that developed on this blog. There is,  I think, room for both in the cut-throat competitive world that is scientific discourse.