There are several significant differenced:
A700 has 6X optical zoom, SD600 has 3X
A700 has manual controls, SD600 does not have aperture priority, shutter priority, and manual.
Physical size.
Batteries.
Here is a look at the specifications side-by-side.
http://www.dpreview.com/reviews/compare_post.asp?method=sidebyside&cameras=canon_a700%2Ccanon_sd600&show=all
They are priced the same but the A700 has more to offer.
Why?....small cameras cost more to manufacture.
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I don't know which to pick. THe Canon Powershot SD600 or Powershot A700. They seem the same almost. Need help? I do not care about weight or size really. Anyone know or have any other suggestions for cameras? (LCD size important w/ optical view finder)

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