Is it better to wait to buy or not?

You really need to know what you're buying and whether prices usually drop at this time of year - otherwise waiting is just putting off a decision for no real reason. If you need it now, buy it; if it's just "maybe it'll be cheaper," you'll end up waiting forever.

It really depends on what you're buying - like, if it's some electronic or trendy clothing, prices can drop pretty fast after a few weeks, but if it's a basic product or you want it now, just waiting for the sake of waiting is stupid. The real thing is to check the price history over a few months to see if there's an actual downward trend, otherwise you just end up putting it off forever.