The T30 appears to be an improved T9 with an extra megapixel. And of course, they both have image stabilization.

The picture quality of the W70 appears to be the same as the other two.

The T30 and W70 use different lens types.

The W70 has a slightly brighter lens which would be a wee advantage in low light situations.

I don't see image stabilization doing much for me on a 3X optical zoom camera.

I would probably have to toss a coin.

http://www.dpreview.com/reviews/compare_post.asp?method=sidebyside&cameras=sony_dsct9%2Csony_dsct30%2Csony_dscw70&show=all

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