First, there will always be some rumored product coming out soon that will be more advanced than today's. When you're ready to take the plunge, take it. Waiting will keep you always waiting and delaying. If the new stuff is that much better when it actually comes out, you can always sell what you have and upgrade.
Next, there is a book due out in about two weeks that I strongly recommend (because I had its predecessor - I have no financial interest here). It is written by David Pogue, former N.Y. Times tech columnist. It is called "Switching to the Mac: The Missing Manual (Mavericks Edition).
1 on sberman's advice about waiting. No one knows for sure what the 2014 MBA's will have (my guess is that they will have retina displays - but that is just a guess based on what Apple have done with the MacBook Pros). The big development has happened in 2013, and that was Haswell with its much improved battery life.
As for adapting to Mac, well I used PCs from the very early days in the 1980's until about 2006, when I got a Macbook. Took me no more than a couple of days use to get to grips with the basics - Macs are very intuitive. I am now 100% Mac with iMac, Macbook Pro and iPhone. Wouldn't go back to a PC for all the tea in China!!
There are big differences from Windows, but you are already doing the learning about many of these and the aforementioned intuitive nature of OSX is such that you will adapt faster than you expect.
MS Office for Mac is very similar to the Windows version and should feel familiar from the start.
I also recommend David Pogues books, he produces some of the most readable and informative guides to the Mac and OSX.
You may find some, if not all, of the following both informative and interesting:
Macs are cheaper to own that PCs: http://techpatio.com/2010/apple/mac/it-admins-total-cost-ownership-mac-less-pc
Why will you love Mac? http://www.apple.com/why-mac/
- Better Hardware http://www.apple.com/why-mac/better-hardware/
- Better software http://www.apple.com/why-mac/better-software/
- Better OS http://www.apple.com/why-mac/better-os/
- Better Support http://www.apple.com/why-mac/better-support/
- It's Compatible http://www.apple.com/why-mac/its-compatible/
Switching from Windows to Mac: