As a graphic and web designer myself, let me say that your web designer/author has done an excellent job with this site. For ease of use and functionality - its great!
I'm am very much aware of the tremendous time and effort involved in both creating and maintaining such a site - and I would hazard a guess that this is more a labour of love for your designer as opposed to a project that will see them paid mega bucks and secure an early retirement to the south of France!
Congratulations for your dedication!
That being the case, please accept my comments on the reskin in the goodwill they are intended.
The problem with running a dark background, especially in a 'framed' format is that optically it will dominate the site and everything within the frame will immediately look smaller and overwhelmed.
This is particularly true with text on a lighter background surrounded by a strong framing.
The previous format looked much less heavy and was a lot easier on the eye - which was largely due to the use of white space. In saying that though, I probably would have just looked at creating a stronger header and leave the rest more or less as it was.
I have a rule of thumb for my design staff..... 'Content is King'
If the design/graphic treatments get in the way of ensuring the legibility of the message - then perhaps a slight amendment might be required.
Well - that's my two bobs worth
Great site people! Keep up the fantastic work!