Let's say I want to trend all comments posted on a site and create dynamic tags. For example, If there are x number of comments that contain the word iPad I would like to create automatically create a tag called "iPad" and put it in a tag cloud.
Is this possible? I checked out the acts_as_taggable gem but it requires one to specify a tag, I guess I am looking for a way to generate tags from content.
Sure, this is possible. Just parse the content of each comment as it's passed in and attach the tags you're interested in.
This can either work on a whitelist - where you specify all the tags you're interested in and attach those if relevant.
Or it could work on a blacklist - where you specify all the words to ignore, e.g. "the", "on". This approach is probably a lot more time consuming, but would allow for more dynamic results.
I would probably work on a white list, then have an ability to add new tags to the whitelist and have it go back and retroactively add the tags where applicable.
Well something like the yahoo term extraction service might do the trick and there is a plugin for it http://expressica.com/auto_tags/.
Though it is not for commercial use.