I thought I'd start this topic after reading a post on the yellow forum where someone inadvertantly put the wrong card in their camera and formatted it

As soon as you realise your mistake, take the card out of the camera - your images may still be on the card as formatting just clears the index file that records where the images are on the card. If you have taken some pictures, you might have lost some of the previous images as they will have been overwritten by new ones.
Formatting a large SD card would take several minutes at least if it cleared the whole card.
Google "recovering formatted SD card" or something similar and you'll find several pieces of software that will recover images that are on the card.
This may also work with cards that have been corrupted.
Fortunately, I can't recommend any of these applications as I haven't made this horrible mistake - YET!