As for the Studio line itself, it sounds like what we heard before was about right: Dell's fast-tracking it to be their new higher-end consumer brand (more here and here). Check out their internal description:
"The Studio line is a more feature rich version of the existing Inspiron line. This series of computers features more multimedia functionality, better processor offerings, and more personalization options than the Inspiron series. Dell continues to sell Inspiron systems, but these are now considered our value series computers for customers who prioritize cost above features. ... Being able to choose from a series of color options and a wide range of hardware offerings helps personalize each system to the buyer. The Studio series is expected to be the best selling line of notebooks for the Consumer segment."