Vis3R - 8:45 pm on Apr 16, 2007 (gmt 0)

Hello,
I can get image links, linking back to my website from other websites (on-topic content). I know it's going to do only good if the sites are on-topic and good websites, but I'm wondering if there's a big difference between a text link back with a keyword in the anchor text or an image link back with a keyword in alt.