Here is a side-by-side look at the specifications:
http://www.dpreview.com/reviews/compare_post.asp?method=sidebyside&cameras=canon_sd300%2Ccanon_sd400&show=all
If you shop around a bit, you will find that the difference in price is only about $50.
Newegg.com shows $305 and $354.
I looked at sample photos from each camera taken of the same scene and the SD400 was better due to its greater detail from the extra megapixel.
I would say, go for the SD400.
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Hey there. I am just about to purchase my first new digital camera in 4 years! I was just wondering if i should save some money and go with the SD 300 or pay the extra $100 or so for the SD400. Is there a huge difference between features or picture quality?? I am also considering the Nikon coolpix S1. Thanks a lot in advance!

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