When it comes to cameras, digital SLRs are a breed all their own. Many DSLR owners don't upgrade their bodies often -- if at all -- and even fewer would consider a switch to a competing camera system, especially after investing in a handful of high-end lenses. Manufacturers need to push innovation even further to target this segment of the market -- when some cameras cost thousands of dollars and already offer excellent performance, simply releasing a body with more megapixels and HD shooting options won't prompt photographers to pull out their credit cards. With its excellent 24.3 megapixel sensor and high-res OLED electronic viewfinder, however, Sony's $1,399 Alpha
