It really is a great application I used to use Photoshop and Bridge to manage everything but I tried Lightroom and couldn't believe how easy so much of it was.
Regading your backups and your Catalog which I mentioned above, sorry if I'm about to sound like a tit, but I think you might have misunderstood either me or how Lightroom works or I've misunderstood what you just said. The reason I'm willing to look like a tit, is because this part of Lightroom is the most vital to understand above
everything else.
You are backing up your RAW images, so you have them in two locations. This is perfect. In an ideal world one of these locations would also be on a different HDD in a different house. All depends how much losing your images means to you.
However, what I'm talking about is Lightrooms Catalog, not your actual images. When you import an image into Lightroom and make some edits, that file actually doesn't get edited at all. Lightroom saves all of those edits into a database called the Lightroom Catalog. This is how Lightroom can non destructively edit all of your images, it never actually writes to the files in the first place. They will forever remain the image your camera made.
What I suggested above is that you back this Lightroom Catalog up. Why? Lets say you sat there today and started going through your extensive collection of images and edited say 100. If you managed to delete your Catalog, or it got destroyed by a virus or god forbid your HDD died, you just lost that work and those changes. You might very well have backed up your images, but without Lightrooms Catalogue those images will go back to being exactly what you shot, without any modifications.
Now imagine you have a Lightroom Catalogue that has had 30,000 images added to it, with many many edits, virtual copies, flags, ratings, keywords, etc etc. Now I delete your Lightroom Catalog.
Now all you have are the 30,000 images you originally took, with no modifications at all. None. It's back to the start with everything.
This video from Adove.tv will show you how to do it in LR4, I imagine it's fairly similar in LR5.
http://tv.adobe.com/watch/learn-lightroom-4/backing-up-your-catalog/
Please please please make sure you are doing this!
In addition, some of those other Adobe.tv videos can be very very helpful when you first get LR.
http://tv.adobe.com/show/learn-lightroom-4/
Apologies once again if all of that is already known to you
