I'd like to point out a few things about AuranJet as firstly alot of people are misinformed about it, and secondly there's some flaws about it (which have really made my day painful).
AuranJet isn't what i'd consider a "game engine", its more like DirectX on steroids. It basically provides a great many common functionalities that 99.9% of games require, but they aren't part of any low level API (scenegraph, skeletal animation, archive file formats + transparent access, etc).
I have a few gripes with Jet,
1. the current JetApi can't compile under VC7
2. the documentation is awful (thank god for the super active forums)
3. some aspects of the api 'encourage' hard-coding parts of your game, worst one i've seen yet is the default animation system which deals directly with files
4. using stl in a program that uses jet is quite an ordeal
5. you will ALWAYS get link warnings... you cannot escape them!
aside from those 5 problems, i fully endorse jet as an awsome thing... full of goodness to a degree that meets my highest expectations.
For the time that I've worked with Auran Jet I've come up with a few gripes as well:
1) Jet exclusively deals with a lot of files, thus its data-driven, which is a good idea sometimes but bad in so many others. This restricts the users (programmers) ability to create game data on the fly (program generated textures for one thing).
2) The documentation is missing a damn few things, and considering it's the *official* API then that's a serious issue. You need to actually look through the Header files to find out fully what is supported etc.
3) Some of the lower level / common functionality is missing - removing / deleting directories in particular - not that you'd want to use it all the time, but the API doesn't feel complete without it.
4) The graphics system is tied too closely to the configuration file structure and options, as in you can't change it from inside your program, which is irritating.
Overall though its not that bad to work with, the User Interface section is quite easy to learn, it has (all?) most of the necessary container types (so there's little need to use any STL stuff). Even though it cannot compile with VC7, I'm sure that everybody that has VC7 also has VC6 so I don't see that much of a problem.
Can't wait to see what they do to V2.0 of Jet.