As soon as you visit the page here, and you are logged in, your "last visit" timestamp is set to the current time, even if you do not look at the forums. This happens, as your account is active on the whole page, and not just the forums part.
Would it be useful to get this changed, so the last forum visit-time is another one then the last visit regular one? I mean, can get that changed somehow, might need a couple of days though, pretty busy currently here
As an alternative, if you visit daily that is, you could use the
View Today's Posts function, as it can be found on the forum index page.