I have clicked on a few threads, reloaded the page, and the number of views hasn’t changed. Is it that my views don’t count, or is it done periodically?
SSG Schwartz
It’s usually done periodically by vBulletin, and there may also be caching involved.
Plus, there may be a special filter put in just for certain users, but I can’t say for certain who is on the list. 
What he said, pretty much; it’s a background thing.