Gearbox is working on a sequel to borderlands, it's going to feature new terrain like snowy mountains and grassy hills, and new weapons and characters, the characters from the previous game will be in the sequel, but only as NPC's you meet in your playthrouh, they're shooting for a mid 2012 release date.
Yes, I heard of the second borderlands on steam news. I read it and I give it a First borderlands had A-ton of fun gore and epic gear (treasure) Side quests were also fun too of the first game. I hope in the next squeal of borderlands has Character Making were you get to make your very own Bad-ass Hero. Also with class picking which will define you Character shape, For example "Gunzerker" person (I forgot his name) his shape can be used as a gunzerker, That is if you pick it :P. Well that's all can say.