Yeah, it's in the screenshots. Cute little utility.

suggestion: maintain a local cache of usernames I frequently upvote/downvote/ reply to/whose links I click. Special highlight for threads in which I have already commented or in which my top X posters are participants.

Screenshot doesn't really tell me how it calculates hotness. HN already uses some form of hotness based on points/time, but this uses a different formula I think.

It looks like it simply uses the number of comments for highlighting comments links, and the number of points to highlight points counters.

Yeah seems that way, I just saw two comments with the same number of points but significantly different posting times and they have the same color. Thought time might be factored in too, like HN does points/(time since submitted)^2.

Also noticed that it doesn't differentiate between positive and negative scores. A score of -4 is hotter than a score of 1.

Thanks! You just found me a bug, I am going to fix it :)