I here what your saying.. i guess as they're renowned for being industry standard.. It will be used solely for photos.
Photoshop, or Lightroom is exactly the same on a Mac as it is the PC. "industry Standard" is just a legacy from when there were very real differences between platforms. Sure, Mac OS and Windows are different, but you're already used to Windows, so why give yourself a learning curve you may not need?
PC hardware is cheaper and more powerful on a pound for pound basis too.. and more upgradeable, customisable.
I'm not saying don't get a Mac if you want one, but if the reason you want one is because they're "industry standard" think again. It will do nothing for your photography or workflow, just because it's a Mac.
As for the mac vs pc I see lots of reasons to move over. Mac = no antivirus, and that is already very significant. User interface is so much better (I've had plenty of time with win, linux and mac), and you get full *nix compatibility as well, can compile your own things with ease, etc. Upgrades are dead easy - just plug in your backup disk and new machine is fully restored, simply amazing
Macs get viruses, hence why you can buy anti-virus software for the Mac. Historically Macs didn't get them because no one bothered to write them for the Mac. That's changing. Carry on with your head in the sand if you want.
Upgrades are easy? Ok.. go and buy a new 22" iMac and upgrade the RAM then... I dare you
Back up? My PCs back up automatically and incrementally without me doing anything... the server also mirrors and syncs to another server, also without me having to lift a finger. What makes you think easy back up is exclusive to the Mac?
I use both. PCs at home, Macs at work. There's no great difference for most people... except Apple's are designed to look nice rather than be truly functional.
User interface? Well.. Windows can look exactly as you want it to. Mine is all monochrome, with custom key mapping and a dock just like Mac OS. It's the best of both worlds.
And the final reason for me... price. To get a Mac as powerful and featured as my PC I'd need to spend over £4K.. without the monitor. My PC cost me just under £2K without the monitor, and it's faster, looks better, and I can use much more high end components, more easily and cheaper.
Basically.... to the OP. Go to the Apple store and use a Mac for a while... see if you like it. If you do, buy it, if you don't, don't. Simple as that really. One way or the other, the applications you will be using for Photography will be the same if you're using Adobe products. If not, then you also have much more choice of free software available for image editing on the PC than you do the Mac.