Yes it is normal and makes sense - both iPhoto and Aperature can open both libraries - there is no need to have seperate libraries - you can do anything in either iPhoto or Aperature to the same library
Does this sound normal? Should I / Can I change the name of the library (to avoid any confusion, since I'll be using Aperture for my photo organization and editing needs), maybe change the name to something like "Steve's Photo Library"? Do I / Can I change the type of library to an Aperture library? Is any of this necessary?
Yes, it does sound normal as Larry explained, see Aperture 3.3: Using a unified photo library with iPhoto and Aperture
Can I change the name of the library (to avoid any confusion
And yes, you can change the name of the library, and it may be useful, when you are working with more than one library. Aperture shows the name of the library it is currently browsing in the library inspector pane. This way you will notice, when iPhoto or Aperture create a new Photo lIbrary; this sometimes will happen, when the drive with your Photo Library is offline.
To change the name of the library, select it in the Finder and open the Info panel by pressing the key combination ⌘I (or use "File > Get Info"). Then disclosse the "Name and Extension" brick and change the name, but not the file name extension.
Do I / Can I change the type of library to an Aperture library? Is any of this necessary?
You cannot simply change the type of the library and better not try. It is nececessay to know the original type of the library. If you look at the document LarryHN pointed to (scroll down to the last paragraphs), you will see that some of the library items you created in iPhoto cannot be read or changed in Aperture. You will need iPhoto to browse or edit your older iPhoto Print Products, etc.
Also, remember to reveal all images that you have hidden in iPhoto, before you switch to Aperture. his cannot be done in Aperture.