Revish is described as "a place where people share their reading experiences", and at first glance looks similar to the many 'social cataloging' or book-based social networking sites that already exist, such as market leader, LibraryThing. However, although the differences maybe subtle, Revish claims to place a greater emphasis on 'quality' reviews, and allows users to network based on what they are currently reading, rather than the books they own. In fact, the site's FAQs advises users who want to catalog their book collection to sign up to LibraryThing or Shelfari, and Revish utilizes LibraryThing's API so that every book review links to the equivalent page on LibraryThing.
So how does Revish attempt to get users to write better quality reviews? Firstly, the site publishes a set of guidelines for reviews, and in addition there is a minimum length -- "at least 250 words... and probably no more than 1000". The idea is to eradicate one-liners and encourage more in-depth critique.
From a technical point of view, Revish also has some interesting features. The site uses microformats for both reviews and users, and 'machine tags' can be employed to pull in appropriate photos from Flickr. What this means is that any image that has been triple tagged on Flickr -- using the format of "book:isbn=xxxxxxxxxx" -- will show up next to that book's review (see this example). Pretty poweful stuff which could become very useful if machine tagging takes off. Revish also has its own API, revealing the site's long term ambitions to become an open repository for structured books reviews.
Revish has entered a very crowded space, but with its emphasis on 'quality' reviews (achievable through some simple social engineering), employment of microformats and machine tagging, along with playing nicely with others (though utilizing APIs) -- its chances of success looks promising.
If you are a company about to launch an exciting new social web service or product and would like me to take a look, get in touch.
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