Not currently, but I could look into adding them as a setting like the WOT icons. What provider would be best?

You can try using Thumbshots. Only works on top-level domains though, and it's pretty low resolution.

Just set "http://open.thumbshots.org/image.pxf?url=WEBSITENAME" as the image location and Thumbshots will give you a screenshot of the homepage of the website you specify.

For example, "http://open.thumbshots.org/image.pxf?url=http://duckduckgo.com" gives you a screenshot of the DDG homepage.

needing something like search(google)preview addon for firefox.

Yah, someone should make an add-on which performs this task.

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I love programming and playing the piano.

I have seen this before and it might be a great option. I would not want to sacrifice WOT ratings but I might be willing to give up favicons, Either way I think it should be an option. Although an add-on might be cool, I think I would prefer a simple option in the settings.

AFAIK, Google only generates the screenshot when the user actually clicks the preview link. If that's all, and noone else provides screenies for everything, perhaps DDG could just generate them themselves?