Well, in order for a page to seem more vibrant, it has to appear to have multiple things happening at once...which is accomplished on the Chronoshock website by using large fonts for titles (which segment the frontpage) and dissimilar colors used for different sections. It appears, quite simply, to be disjointed.
Also, the Compendium frontpage uses a single background texture that underlies all other textures. This makes it seem as if it's all on a single plane, a single background layer, to use a more emulator-oriented term. Whereas Chronoshock appears to have raised areas (the dark grey) and flatter areas (the black, the text). It just gives the appearance of depth, as opposed to linearity.
Does that make any sense at all?