Coming from an Architectural background and having a strong 3d hobby (using XSI), I would say you're best choices for an Arch viz advertising campaign are:
www.cgarchitect.com
www.cgtalk.com
I noticed on your 3d World studio, you mention importing:
.x, .obj, .md3, or .gls meshes.
I highly recommend adding additional formats such as 3dmax, Autodesks Viz, any Autodesk product as Architects or arch viz projects many times are born from these products. Microstation, Form Z, Rhino, Brazil imports would also be useful to firms/architecture students. I've used all of these products and they are standard for arch viz.
www.cgarchitect.com
www.cgtalk.com
I noticed on your 3d World studio, you mention importing:
.x, .obj, .md3, or .gls meshes.
I highly recommend adding additional formats such as 3dmax, Autodesks Viz, any Autodesk product as Architects or arch viz projects many times are born from these products. Microstation, Form Z, Rhino, Brazil imports would also be useful to firms/architecture students. I've used all of these products and they are standard for arch viz.