The style is nice. Looks clean and uncluttered and very pleasing on the eyes (especially at 3:30am in the morning). Like shazz suggested, something like a sky scene intergrated into the logo would look nice but the logo you've implemented is more than adequate and looks and feels consistent with the style.
Forum status Icons look nice and (prompt me to register) I'm a little strange like that.
However, I would recommend that you replace the default vbulletin stock images . Maybe concerntrate on replacing the default images on the index page first (lastpost, whos-online, stats etc) and give it that custom look further enhancing your forums style.
There's still alot of other vbulletin stock images lurking throughout the forum and would suggest that you also replace those for something custom giving the whole style a more enhanced overall look.
Nice forum, just needing a few touchups and replacements and I think you'll have a nice theme.
Goodluck with your site.
Edit: I suggest taking a looksy in the graphic Database here atleast that will be your buttonset issue solved.