Is your family in another city or state? Most of mine are in Seattle, and I usually don't go up there during the holidays, because travelling on those days is a nightmare. For Christmas, I do send things up tho, at least for my mom. One trait that she has handed down to me though, is procrastination. So I blame her for my gift arriving late.
If you do plan on sending Christmas presents home, the United States Postal Service has released some dates to help you in making sure your gifts get there in time.
Check out the 'send by' dates.