Here's Russell Brown explaining how to protect details with Content-Aware Scale tool options. There's a QT version available too.
In addition to the original presentation of the research on content aware scaling (paper), there's another presentation from SIGGRAPH 2008 that's slanted toward video. Let's hope that some of this will appear in future implementations within After Effects, and maybe even some improved upscaling. Here's Improved Seam Carving for Video Retargeting: