Which brings me to a question: How much extra runtime do you guys think I might squeeze out if I replaced the drive with an SSD? I find it an occasional hassle with the need to carry 3 additional batteries to match the runtime of my Sony + spare battery (not to mention the huge additional weight).
tomshardware.com did a test -- Conventional HDD vs SSD. They got maybe a few minutes extra with the SSDs. A good laptop HDD is pretty efficient when it comes to power. SSDs just aren't worth it yet IMO.