When you do make the move I'm sure you'll be extremely happy.
Around August of last year, I was starting to look around and research what programs I was currently using on Windows and which of them had a Mac version. Too my surprise most had a Mac version, and even ones that didn't, there was an equivalent application available for the Mac which would do the same thing.
I spent from last August till basically the end of 2012 researching on various forums, websites and thinking of questions I wanted answered and posting those questions on the various forums. This really helped me and clarified a lot of things I was unsure of.
My reasons for going to a Mac were:
I was fed up with random issues and just the general unreliability of Windows. (Mac OS on the whole is a very stable and reliable OS).
Fed up with having to run and scan with anti spyware and anti virus programs (Mac's are not immune from virus's, but they are very rare).
Sick of been bombarded with Windows Updates. (You get updates on Mac OS, but these are MUCH less).
With having iPhone, iPad, Apple TV, I wanted to have the integration of the various apps, features to be available to me on my Mac.
A bit of advice I would give you is, if you are not planning on getting your Mac till next year:
1: Look at the current programs you use now on Windows and see which are available in a Mac version. If there is no Mac version available, ask on here or over on the Apple help forums which application they would recommend to use on a Mac for that purpose.
https://discussions.apple.com/community/desktop_computers/imac_intel
2: Any questions or things like that you are unsure of about Mac, have a look around and see if they have been answered and if not, post that question on here and on the Apple help forums.
Various things about Mac are similar to Windows, but somethings are very different. When you get your Mac, learn the Mac way of doing things rather than trying to do it the Windows way
The good thing with Mac is, you can have the best of both worlds, i.e. install Windows on your Mac.
You can do it a couple of ways:
1: Mac OS comes with a application called Boot Camp. Essentially this allows you to partition a portion of your drive and install Windows on it. To load into Windows, you restart your Mac, and you hold down the option key on your keyboard, during the restart you will have a screen shown that shows your Windows installation, simple choose this and your Mac will load into Windows. To then load into Mac OS again, restart your Mac, hold down the option key, and then choose your Mac OS from the screen. Most people agree that running Windows through Boot Camp gives you the best performance of Windows, but at the inconvenience of needing to restart your Mac to boot into Windows.
2: If you want the flexibility of been able to run Mac OS and Windows side by side and without needing to restart your Mac. There are a number of applications that allow you to do this.
The most popular tends to be Parallels Desktop (this is the application I use). Although I have never used Boot Camp (so I cannot comment on the performance of it). I find that performance wise, Windows runs extremely smoothly with Parallels Desktop. With Parallels Desktop, you can be doing something in Windows and at the same time be working on something on Mac OS.
One thing I would recommend if you are going to be installing a virtual machine, i.e. Parallels Desktop, is to get plenty of ram, as virtual machines/Parallels Desktop can use quite a bit of ram.
Depending on what/if you will need Windows, then you at least you know that there options open to you that will allow you to run Windows if you so require.
I'll provide below some links to some useful articles that helped me when I was researching:
https://forums.macrumors.com/posts/9848667/
http://www.apple.com/support/macbasics/
http://www.apple.com/uk/findouthow/mac/#switcher
http://support.apple.com/kb/HT4527?viewlocale=en_US&locale=en_US
http://www.danrodney.com/mac/
Hope this helps