EDITS ADDED
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(1) Scroll to the bottom of the blogs page
(2) Count up 6 blogs
(3) Above that there is a "Hot Now!" label
EDIT: LOL I know it's not hard, but its just two words added in the middle of the blogs so people are missing it and not sure what all the talk is about.
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It has not yet been confirmed how it is determined, but we are assuming by views as opposed to points or comments...
I'm using this blog to TRY to confirm that it's views...
EDIT: I think it must be since this made "Hot Blogs!" with only 42 points and 0 Comments. And many other blogs on the front page at the time had comments and more points.
But it probably got views (without plus/comments) since I made the blog so that you have to click it to see what it says :)
Also, if it is views:
-How often is it changed? Is it most viewed in the last hour? Last 6 hours? etc.