Just throwing this out...well, first of all, I love the first one, so that would be my vote....

I'm not sure how hard it is to change the banner, but I love the idea of the huge mass of trucks. Assuming the banner will span the area at the top of the page that is currently gray, what if you put as many trucks (same size as you have them) off to the sides of what you currently have? If you don't have enough to fill the width of the banner area, I'm sure you would shortly as new members join. As more people join and add pictures, you could add them to the banner. Kind of like the banner would grow with the site. I think that'd be pretty cool.

Plus I want to see my truck up front