"First, on my agenda is to purchase a Canon 100-400L IS to go with my 70-200 F2.8L, both of which are staples of the 20D system I utilize."
I am not sure why the site was loading slowly. We were having a heavy volume of traffic at the time I checked your site out. Perhaps others were looking at it too. I should check the site out from my office. The connection there is slower than it is here at home.
As for lenses - I am constantly debating which lens I want next. The 100-400 seems like a very versatile lens. I know that I see a lot of the in Yellowstone when I am out there.
My next purchase is going to be big though - I am debating both the 300 F2.8 IS and the 400 F4 IS DO. It will probably not be until next year. Unfortunately, for wedding work, I don't have much excuse to purchase any of the larger lenses.

Have you thought about where and what you want to focus on in wildlife photography?
-JM