When I export as svg or pdf the resulting image appears much larger than the original gerber file. I've tried loading the svg and pdf into Adobe Illustrator and Inkscape with the same result so I can only assume the problem is with gerbv. The problem exists with 2.0.1 and 2.2.0 (I've not tried 2.1.0).
2009-04-30 11:17:46 UTC in gerbv -- a Gerber (RS-274X) viewer