My wife-unit has a first gen 2ghz Core Duo Macbook which suites her purposes well still: web surfing, word processing, iphoto import and export to flickr, and HD video processing for export to youtube. Watching HD video (MP4, ABC streaming, HULU). I'd like to replace it with a new 1.6gz nvidia Macbook Air. How do these two stack up? Does the Air still fall behind this 3 year old MB? She'd chuck out the window if it didn't function as well.