Suffering from a bout of nepotism, I feel moved to point my linguistically-gifted friends at a Belgian site where Ewan, described as "tres chaleureux et enthousiaste" by his interviewer, is waxing enthusiastic for eternity in rather rapid French.
Having only recently been bitten by the blogging bug, I share his evangelical fervour as keenly as any new convert - and am convinced of the genre's beneficial effect on, among other pursuits, writing skills. It is so different from casual emails, where missing caps and glitches don't seem to matter; I will go back to edit anything I notice once it goes on site. I have always advocated the keeping of a journal as a way to enhance fluency in writing, but this is a journal with a potential audience - more journalism than journal - and as such encourages care and thought.
In fact - and here I go sticking my neck out - I notice a difference in the writing (in English) of one blogging relative since he started blogging. That's six months of time (so you know who you are ;-)) and would represent a triumph for any English teacher. Pupils often realise that they have to *pass* English to "get on" - but apart from that often express the opinion that they will never need to use it after school (a bit like my own Higher Maths?). I would suggest that in a world of rapid job-change and insecurity, a journalistic ability might well turn out to be a useful asset.
Besides - it's addictive.