My first three children have June birthdays, which has always made for convenient 6-month installments of gifts at birthdays and Christmas. I really prefer that, because:
* It helps kids tolerate delayed gratification;
* It helps stave off impulse wishes (that thing they saw in an advertisement or at a friend's house, which is their heart's desire for a month - so you plan to buy it for Christmas - then they lose interest in it before Thanksgiving, so you wind up glad you didn't shell out $50 for it); and
* It seems to make kids more excited and appreciative about receiving gifts on special occasions, since getting new toys isn't an everyday occurrence.
It's trickier with my youngest, who has a February birthday and must then wait the greater part of a year, for Christmas to roll back around. However, he benefits from his three older brothers' stockpile of toys and Legos, so there's usually something he hasn't played with in a while, that I can rotate into his toy box when he gets bored with what's already in there.
I like to take advantage of garage and clearance sales and will sometimes reward a kid, for tolerating the boredom of shopping with Mom, by agreeing to buy a little something that's, say, 75% off. And if I come across a reasonably-priced educational toy that addresses a skill my kid is working on right now, I'll go ahead and give it to him. But as a rule, anything substantial - even an unusually expensive, non-essential item of clothing (leather jacket or trendy shoes) gets stored away until Christmas or birthday, whichever comes next.
The first time I really appreciated the value of giving things to my kids this way was when my oldest (twins) were in preschool and I babysat regularly for another set of twins. The other boys' parents routinely bought them new toys and it was hard even for *me* to get through a store or exit a museum (past the gift shop door) with them, without what seemed to me like a dizzying amount of begging and whining - even full-out temper tantrums - over wanting things that caught their eye...and wanting them RIGHT NOW. I realized how nice it was, that if my sons got excited about something, their only effort at pressuring me to buy it would be, "Mom!!! Look how cool that is! I'd like that, for Christmas!" or "I'm gonna tell Santa about that!"