The HTC Magic currently runs Android 1.6 but is supposed to be getting updated to 2.1 soon. Android 1.6 is a great experience as well though, just not quite as pretty as they have made 2.1. You have your three home screens to fill with apps and widgets as you please, and the pull up menu for your full app list. Also, all of your notifications can easily be seen at the top of the screen with the notification bar, it too can be pulled down to expand on on all of your notifications. It will also display current actions for some programs such as, if you are playing music, what song is playing among other things. Here is an example of what could be on your three home screens.
There are various apps and widgets there. A couple of the pre-installed widgets are the Google search bar and the power manager widget that gives you quick access to turn some power hungry features on and off. Note that the power manager widget on this screen may look slightly different than your pre-installed one due to some modifications from Cyanogen. Something else that is of note is another feature called Live Folders, they stay up to date and can include RSS feeds or other items such as your contact list. There is one from Facebook that allows you to call your friends using their number stored on Facebook.
Another neat feature is the ability to multitask and run multiple apps at the same time. There is even an easy way to switch between them by simply holding down the Home key. When you do that it shows your six most recent applications.
The settings menu is very accessible as well, just press your Menu button from the home screen and you will have access to the settings on the Magic. You can hit the Menu button while running any other program for that program's options and settings.
All in all, Android is a very easy to learn and intuitive operating system. It has many great features and many great ones on the way in future updates for the HTC Magic.