You want my honest opinion?
There is no better. Ever. Only the proper tool for the proper job. Some people prefer Win, some Mac, and some Linux. They all work well, and they all get the job done well. Some are better than others for specific tasks but in this day and age they're all pretty much equal.
It all comes down to a matter of preference.
If you were looking to pick OSX over Win7 or Linux however, you'll undoubtedly find a whole array of opinions against that, more-so than the other two, since it seems that there's a general trend of extremism surrounding some people's tool choice.
Some of the general "complaints" read on the Internet are by people who aren't very computer literate, and simply don't know the truth, and would rather espouse idealistic and falsified "truths" about the OS than learning more about it.
To be honest, you can do just about anything on OSX that you can do in Win7, only the methods are different. Desktop customization is quite possible. Enhanced options, command line functions, back-door fiddling; all possible. The OS is there, you can always run in root and modify it, or use sudo, or just replace files.
In general, I find OSX to be far more simplistic (but not lacking features if you know where to find them), streamlined, and easier to use than Win7, with a perceived speed increase in day to day use under OSX over Win7 with similar hardware.
That said, hardware is where it's going to get you. Win boxes always have better hardware, and also have a lot more cutting edge support for such. Driver updates are common, and while not always stable, will provide large performance increases. Gaming under Win is far better than OSX. Graphics cards perform better, and hardware can be tweaked (ie over clocking) via the BIOS. There's generally a larger gap in customization in this sense, as OSX is very hardware locked in, whereas Win supports complete hardware customization and frequent upgrades.
If having the cutting edge isn't important to you, at least in terms of hardware, then I'd recommend OSX. In my opinion their OS is far ahead of Win7, still, but remember, with each pro comes its con, which is why they're all about the same. If OSX were to get better graphics drivers, frequent updates, and be more supportive of over-clocking and DIY installs then I would hands down recommend it, but since this isn't the case I would say its really your pick, since there is no "best."
