On the editing issues, I hear you loud and clear. My current laptop only has 1 gig of RAM and the RAW conversion software really struggles to process the RAW files. So, I will be upgrading some time in the next several months.
I've also learned that one true difficulty of working off the laptop is the LCD screen "tilt factor." If you're not viewing it straight on, color and saturation can look dramatically different.
I'd be interested in hearing whether others only use desktops for editing their images or hook their laptops up to a desktop sized monitor for editing.