The best way to engage people on social networks is through images. Facebook's most engaging type of content is its images. Ordinary profiles and pages have found that people engage with images more than any other type of content on the site. This also goes for Tumblr, where over 40% of content posted on Tumblr blogs are images. I've said many times before in other posts that posting images is the best way to engage with fans on fan pages. I do it myself with the UltraLinx fan page, you'll see that I post images quite often and they always get a lot more likes and comments then anything else posted.