Would you consider this behavior indicative of romantic interest?

While he is not periodically sending me cakes, unfortunately, there is a guy in my department at school who has exhibited strange behaviors that tread the fine line between friendly and showing further interests. I know him from around; we don’t have any classes together, but we see each other on average twice a week in the lab. We talk a bit, mostly about whatever we’re working on, and the conversation is certainly comfortable. Then one day out of the blue, he comes in and walks right up to me. He sets a book in front of me, quickly says “I got you a book,” before he turns around and immediately walks away, before I can thank him or even say anything. The book is called Bad Girls and Wicked Women, and it is a collection of short biographies of notorious ‘powerful, shocking, amazing, thrilling, and dangerous’ women in history (think Catherine the Great, Cleopatra, and Imelda Marcos). It’s a very nice book, and, according to Borders online, costs around 40.00. He also went out to grab dinner, and offered to pick something up for me. We wanted the same thing, and when the restaurant only had one left, he gave it to me and got something different for himself. The next week, I was going out with two classmates, and we invited him to come with, but he declined. That was all well and good, but when we got to the restaurant and ordered, he appeared five minutes later to eat with us. He also took a shot with me once in the lab (yes, yes, drinking at school is bad, I know), but hasn’t, or at least to my knowledge hasn’t, offered any to anyone else.

So what’s the verdict? Am I just reading into friendly gestures? Or are these gestures of a grander kind? I haven’t seen him in about two weeks, just as a function of our schedules, so I’m wondering whether it would be worth it to make the first move, wait for him to make the first move, or wait for more evidence.