Hi Zartan -
I don't like to make any of those notices unable to be clicked off. The only ones I have like that are mandatory ones like "you still need to register your email" or "your PM box is 90% full". Anything that's just a general announcement should be under the control of the user to remove when they want.
The reason I think this is important is that users have very different screen resolutions. I've got two huge monitors, so that one line doesn't really take up much screen real estate for me and it doesn't bug me at all. Someone using this site on a laptop at 1024/768 or even a netbook at 1024/600 resolution may be sincerely cheezed off at having an extra line of text at the top of every page that they can't remove.
I do want to continue to promote the wiki as much as feasible though, which is why I added the link right in the navbar, as well as a link from each tech area. While I hope that it continues to get more use (I haven't seen a new article from anyone but me in a week
), I think it now has enough links on the front page that it's no longer a matter of people just not knowing about it. I also try to remind people within threads if I thinik it's an appropriate place to mention it.