Wow, that's really nice if he means it, either that or he's one of those that just says it without meaning it, but it sounds like he meant it so good!
That last sentence was wrong...anyway!
I've been going of with my bf for 18 months and we still both find it difficult to say we love each other, I think I'm in the position of still caring deeply for him, but I don't know, it's not exactly love yet. Not that our relationship is bad or anything, we're both very happy, but I deem love as being the big whammy, the big I want to spend my life with you type of thing. Anyway yeah, you don't have to say you love him back if it would be a lie atm, but let him know you care and like someone else said, make him feel at least special to you.