How many pictures will a 4MB memory card hold on a 9MP camera?

Surprisingly, my Canon Ixus 75 (7.1 megapixels) seems to think it can take 1271 pictures on a 4GB card at the highest quality level.

For any thing you need to know about number of pictures a card can hold or amount of video it can record, go to:

http://www.picstop.co.uk/pdf/image_count.htm