There are currently two main ways of producing microcontent. One is using a desktop blogging client and uploading the content directly to your weblog, followed by pinging a number of aggregators, which spider your content and add it to their index. The second is using external sites (eg Flickr, del.icio.us) to format and store your content, then either posting it back to your weblog from there or producing a feed that can be aggregated back into your own page.
Steve Mallett (datalibre) seems to be in favour of the former, where everything is hosted on your own site. Marc Canter (ourmedia, peopleaggregator) seems to be in favour of the latter, where you add your content to various distributed communities and use your own page as a ('digital lifestyle') aggregator (though confusingly Eric Sigler's PeopleAggregator diagram seems to lead more towards the datalibre style of publishing).
I started off making RVW as an extension to RSS/Atom feeds, with the idea that sites like AllConsuming and Technorati would spider everyone's sites and pick up the pre-formatted reviews. The problems with that are that a) that's a lot of spidering, at least while you aren't able to directly ping the aggregating sites with your formatted reviews, and b) most blogging tools weren't well suited to storing all kinds of metadata.
However, I also made a review formatting tool that posted a finished review to a) your weblog and b) a central aggregator site where other people could browse everyone's reviews and subscribe to particular categories. Even later, a newer version of this tool also posted reviews to del.icio.us, from where you can aggregate the list of reviews back into your own site, rather than storing them there yourself.
Personally, I think that storing microcontent on various specialised sites and aggregating the data on your own page is the best approach at the moment, based on the limitations of current blogging tools and pinging and spidering arrangements, though this could easily change in the future. Just make sure you don't store any content in a system that doesn't let you export it back out again. For constantly changing data like FOAF, however, over which you need to retain control, it makes sense to store the file locally and have others reference it when needed.