Well, I'm both seeing it in the ebook and pbook arenas for myself and the others I talked with, so I can't think it's unique to ebooks, although I can easily see how ebooks would be affected by this time of year.
Now one period of time I'm looking forward to is tax time. Why? Simple. People have money, and all that pent up spending urge goes into full swing. The March/April/May period is probably my biggest three months of the entire year. Books fly out the door like crazy during that time.
