dcjp02:
After launching ArchiCAD 10, go to Help > ArchiCAD 10 New Features Guide, which will open this pdf file. It contains information about the new features, as well as advice on migrating ArchiCAD 9 & PlotMaker 9 files to 10. This is a good place to start.
You should add a Signature to your Profile (click the Profile button near the top of this page) with your ArchiCAD version and operating system (see mine for an example) for more accurate help in this forum.
David