What a great start! Rated 4 out of 5 stars
Thank you Oleg for this amazingly sleek addon. URIM even seems to know stopwords in different languages.
Please also have a look here:
for a tool that does automatic keyword collection and highlighting.
Maybe you can provide a similar option for URIM, for example, use the most frequent words from URIM's tag cloud, and highlight these words in the web page text with different colors!
Keep up the great work!