http://www.gamesradar.com/xbox360/batman-arkham-city/news/batman-arkham-citys-comic-con-trailer-has-penguin-and-suprise-guest-solomon-grundy/a-20110722122441539052/g-20091214174528870002
Shows some videos of The Penguin and Solomon Grundy. I haven't taken the time to figure out the new forums. That's the best way I could give it to you. Sorry.