From the plugin creator:
the latest .7 version introduced probably some weird behaviour in the wpfavcions_uri table since I noticed that some URI's had multiple entries.
I could not reproduce this on my local host but I did notice it on my weblog (http://edward.de.leau.net). This is a pretty big blog with 10.000+ postings.
Anyway for safety i turned the cache off in 0.4.8. You can delete the current cache via the regular "clean cache" option.
I hope to have found the issue and resolve it in 0.4.9. but that will be later next week.
Yes... its a beta.