i've had many an iPhone & love my iPad, but have always had a windows pc as the backbone of the system. it's dying so to complete the ecosystem, got my 1st mac. any suggestions as to enhance the experience, i.e. maintenance or utility apps. what ever software advice or wisdom to bestow upon this group
First off, if you haven't, buy AppleCare. I don't care what Mac it is, AppleCare is essential.
Secondly, set up iCloud on it. If your iPad and iPhone are all running iOS 6, you'll find that the level of integration is charming and iCloud is the driving force of that.
If you bought a MacBook Pro (be it retina or non-retina) or a MacBook Air, you'll absolutely want to have "Find My Mac" enabled, though it costs you no inconvenience to have it enabled on a desktop as well.
Take advantage of Mountain Lion's Facebook integration; you'll be surprised by how convenient it is to post and share stuff.
If you are not the type of person to use e-mail clients (by which I mean you go to your e-mail provider's website to check your mail), consider opening up Mail and setting up your mail there. Mail is one of the key reasons I can never switch back to using Windows primarily as it is by far the best e-mail client I have ever used. Setting up Messages for iMessage and/or AIM and/or Gchat and/or Facebook chat and/or Yahoo chat will also make you feel right at home. Doing the same for FaceTime (if it's a Mac mini or Mac Pro, consider getting a webcam as FaceTime is of a much higher video quality than Skype on average).
As far as maintenance goes, just check for software updates once a week either via the Mac App Store or via the Apple Menu "Software Update" option; though most of those updates are reported about on this site, so if you are a regular here, you'll know what's coming out when it comes out. Still though, some of that news can get buried, so it's worth checking for yourself from time to time. Remember, the Mac App Store keeps its "purchased app" updates and its "system updates" separate from each other. Barring that, it might not hurt to get familiar with Disk Utility, which as far as maintenance is one of the most useful stock apps out there. Similarly, if you find yourself with programs that are misbehaving or crashing, Activity Monitor will give you a finer element of control than simply doing the Mac equivalent of Control-Alt-Delete (namely Command Option Escape).
As for getting the hang of the Mac operating system, my strong recommendation is to just play around. When I first went to college in 2003, I took with me an Early 2001 iMac and a Toshiba Laptop from 1999. The Toshiba ended up being secondary as I spent most of my time and energy playing around OS X. It's pretty easy to pick up. By 2005, I had learned more about OS X in my two years of using it than I ever had about Windows in my ten years of using it prior. The thing to remember is that OS X will always prompt you before allowing you to anything truly catastrophic. In some cases, it won't even let you unless you enable the root user. It also helps to bear in mind how OS X is organized on your drive; you have the System folder where the OS itself lives, you have a system Library folder, the users folder and the Applications folder. All of those folders are commonly accessible to all users. Then you have your user account, in which you have a library folder that dictates and governs preferences specific to your user account, your documents folder, your desktop folder, your downloads folder, your pictures folder, movies folder, etc. To install programs, either run the installer, drag it to the applications folder, or download it from the Mac App Store. Bada bing bada boom. Again, just play around and you'll be surprised by how much you end up learning.
If you like the idea of also having a Windows PC, use Boot Camp and you can alternate between using your Mac as a Windows PC or between using it as a Mac. For some, this is handy as all hell. Personally, I enjoy having my PCs and my Mac be separate machines, but taster's choice.
Otherwise, play around and have fun. Welcome to the side with the greener grass.