When I click on a hashtag ... I get this popup.
I was not expecting a popup. I was expecting a page ....
If I right click on a tag link and select "Open in new Windows" I get this ...
this was more what I was expecting.
So Popup vs an Actual Page ... what is the best default action ? Hard to say.
One thing would make sense ... if a user was presented with the popup .... they should be able to click the tag in the popup and be directed to an actual page. What I mean is when you click this..

You are directed to
http://phphelpcenter.com/hashtags/comment/

Hashtags isn't the best Tab name IMO. Admins and Addon authors will like that name. I myself like the name. Forums of less technical users (95%+ of forums) probably would benefit with a tab name like: Trending or Trends or Topics. Being able to change the name of the Tab would be good.
The Hashtags "homepage" felt weird.
http://phphelpcenter.com/hashtags/
I was definitely expecting a list of hashtags to choose from - as would most users.
A list of "the five most commonly used hash tags for the past week" could be an option, but a tag cloud is a better idea.

I think hashtags in the subnavbar is always going to be too cramped.
They should be moved into a cloud. A link called [This week] in the subnavbar would be useful.
There are many different ways that hashtags could be used. Some for fun communication, some for more serious documentation. hashtags for just admins and mods might hashtags more of a documentation tool or announcements. The current design reflects one way of using hashtags .... Hopefully, I have given another way of using hashtags.
Suggestion: enable addons (RM, XenPorta, etc) to support hash tags.
keep up the #goodwork
