In fact, Fortune suggests that those devices may have had an effect on the numbers -- customers coming in to the stores to look at or buy iPhones and iPads may have walked out with either new Macs, or just a better impression of the computers. Back-to-school sales were also very important for the company, and that late July refresh didn't hurt either.
Even if Apple didn't break the 4m mark, it's very likely that this will be an outstanding year for Apple's desktop and laptop sales anyway. We'll know more next week -- Apple's 4th quarter earnings call takes place on the 18th, and we'll be listening live to see what they say.
Edit: A previous version of this post cited 4m as the total for 2010. It's only the total for the 4th quarter of this financial year.