Show HN: book recommender based on any user's tweets - iteration 2

http://foxblot.com I built this site over a weekend two weeks ago.

I've spent this weekend matching tweets to books. If you mouseover a book, it shows the tweets relevant to that book.

Internally, keywords are rated inversely with their frequency of occurrence. The one problem is that my word frequency database does not correspond very well with twitter's vocabulary. To base my frequency database out of tweets is for another weekend.

Please let me know what you think. Specifically: 1. here can I go with this? 2. is it useful? 3. is slowness an issue? (it's running of a 256M rackspace cloud instance)