You shouldn't need anything to hook a camera up to a Mac, not even the software Panasonic provides.
As far as the upgrade, while you would get a better sensor and lens for higher quality images in a wider range of light, the LX5 will not be able to shoot faster than your current camera.
Hi,
<div>I'm considering upgrading from my Canon Powershot SD1100 Elph to the Panasonic Lumix DMC LX5 to improve my ability to take more shots quicker (including pets and kids) and not sacrifice picture quality.

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