How long are pages taking to come up for you? It shouldn't be more than 5 seconds (usually less) or so.
It takes about 1 second. When the user sees a large visible change on the screen, such as a white-out of the list of forum threads when changing
the page number, the user expects a corresponding change in functionality for the better: more information and actions to be exposed. Problems with the current approach:
When I click "next page," I get a big visual change, a white page, but no benefit.
With one action, click next page, I expect 1 visual change, the next page appears. Instead I get two changes, a white page, then the next page. This is a distracting flashing effect if it happens quickly. If it happens slowly, it is confusing.
With a simple, traditional html approach, I can click on existing links while waiting for the server to respond. I can't do this with the current implementation of the forum.
Gmail does show a small "Loading..." indicator when retrieving data from the server. In addition, I believe all links on the screen are still active and can interrupt the loading process. This is ideal. And they use some kind of AJAX. So it is possible in theory.