Usually the guys who block their calendars don't want others to see what they are doing with their lines, like picking up tons of extra trips, etc. That information is still readily available, but it does take a few extra keystrokes for someone to find what you're doing. There really is no way to hide from someone who is determined to find out what you're doing. From what I've seen, it's usually the senior guys, or the guys who are flex instructors, or LCA's who most frequently block their calendars.

Some of the advantages of not blocking your calendar are: a) your friends can see if you're in town (for dinner, a beer, etc); b) someone might want to do a mutual trip trade, or a pdo bump (gives you the days off with pay, except per diem); c) if you have a question about a trip you're on, or one that you're about to fly, and you call FedEx ALPA, they can call up your calendar and advise you more correctly. There are many other reasons to not block your calendar, of course.

I think that for someone whose not been here all that long, you'd want to keep your calendar unblocked, if for no other reason than just wanting to be one of the "guys." Of course it's totally up to you, but do recognize that if you block it, we'll all talk badly about you.