Should I expect increased traffic if I optimize my images?

From my experience the increase in image traffic is offset by users who steal your pictures. I am constantly fighting back against those who use my pictures on their web sites without asking permission. They even still have my visible watermark showing.

A highly ranked image within Google images is nice, but be prepared to spend some time fighting image thieves.

Does the length of the image name matters? For example if you name your image "Should-I-expect-increased-tra ffic-if-I-optimize-my-images.j pg". Sometimes you want to be more specific, so you use a longer name, but does that matter to google or will it just ignore the (really) long image names?

This was an obvious answer.

I have to agree. It is indeed almost clear that if you search for "dog" via image search you will most likely find images named "dog.***" and pictures that are near content that targets a "dog" issue.

I think the more interesting part would be, can descriptive names for images near appropriate content increase my traffic? And how important are alt tags and title tags in this question.

very good as usual

I thanks both of you, Liam and Matt, making this thing very clear because sometime a photo tells thousand of words and pictorial explanation much better than texts. Another fact is a quality photo does edifies many viewers.

That is why I uploaded my photos/images to Picasa Web Album before upload it to my weblog site. Register - Caption, Multi-tagging, people (facial recognition), map, etc.

...unless you wanna rank for the number of the beast on google images!