It wasn't much later that HTC introduced the Hero. In many respects, the Hero was very similar to the Magic, but it has one stand-out feature: HTC's Sense UI. Sense is a user interface overlay that adds a lot of functionality to the Android platform. It opens up more homescreens, includes home-brewed HTC applications for email and Twitter and other UI niceties. When it launched, there was a collective groan from owners of HTC's G1 and Magic, as they didn't have access to this more user-friendly system software.
Now, they do. HTC has made a new version of the system software available that adds Sense to the Magic. HTC recommends that users back up everything before performing the update.
Here's the kicker. Right now, the software is for the HTC Magic -- not the myTouch 3G (despite their similarities). I've reached out to T-Mobile to see if/when Sense will be supported, but have yet to receive a response. That means U.S. users of the myTouch should refrain from updating their devices.
For owners of the Magic, here's the link to download the new system software.