Did you scale your photo yourself before uploading, or let SEOmoz do it for you? My profile image is quite sharp, but I have it pre-scaled to different sizes (nicely, from Lightroom/Photoshop so the sharpening is nice) so I uploaded it at approximately the right size. Your's looks a bit blurry, but maybe you uploaded a really big image?
As for the screen - it depends what monitor people are using...
Just an idea. Either way - I still suggest we all stop worrying about it. 