Yes that's true, Apple has an history of being a very good work tool for both musicians and visual artists, but that has changed since they released the Intel Macs. Right now you can compare what's inside and choose according your needs.
For Visual Artists, besides a powerful processor you'll need a good Graphic Card and tons of SDRAM and VRAM. You can find that on Samsung's Series 3 or 7 laptop with very good results. All the visual arts software you are used to in a mac has now simultaneous releases for both platforms which means you don't need to leave behind all your past work.
Apple computers quality has decreased much since the Intel Mac release, costumer support too and also their policies aren't as friendly as they used to be. Samsung on the other hand has improved not only technically but as a love mark. Their Galaxy Note Tablet and Smartphone are technically way better than any incarnation of Apple's iPhone and, Visual Artists, don't forget that it's the only mobile device with an Adobe Photoshop Touch developed specifically for it.
So if you're looking into a new laptop, remember that Apple, that used to be an awesome professional tool, is now only a status symbol for the super rich. Choose a better machine for one third of a MacBook Pro among the Samsung's Series 3, 5 or 7 according to your real needs, and be sure to be making a good choice. Remember that a more powerful computer will have better results with the software you need to run.
About changing OS... Yes MacOS X is awesome, but Windows 7 and 8 are amazing and have a great UI, very easy to adjust after over 20 years of Apple Computers, the migration is relatively painless and will save you a lot of money. Think different, don't be an iDiot!
