XDA user spacemoose1 is very close to having a working version of Honeycomb on the original Samsung Galaxy Tab. He's been documenting his efforts to bring the SDK build of Android 3.0 to Sammy's 7-inch tablet over the past couple of weeks, and he's very close to having a full, working port. Recent progress has involved correcting video driver issues, and spacemoose is now turning his attention towards fixing up touchscreen and Wifi support.
This is all pretty impressive considering the Honeycomb source code isn't even available yet. If you're a Galaxy Tab owner with a nagging case of Xoom envy, then you'll probably want to keep watching the source link for further developments. [XDA]