httpwebwitch - 9:59 pm on Aug 28, 2009 (gmt 0)

I can't see how it could hurt from an SEO perspective. If you want to do it, do it. I also can't imagine why there would be a penalty for linking from one page to another. That's what the interweb does. That's how PageRank works. And that's why trackbacks exist.

From a traffic control perspective, people might click over to look at your competitor, and like their site better. So... open the link in a new window or tab so yours stays open. ;)

You could also frame up their site the way other portals do - leaving a "go back to my site!" strip across the top. I hate those things, but they do serve a purpose.

Think about your users. Does it enhance their experience to have links to your competitor?