Before I got my Galaxy Nexus, I was a die hard user of GO Launcher EX. I was actually reluctant to try it at first, but a good friend of mine basically forced me to use it for a day, after which, I never looked back (Thanks, Chris!). I can't imagine having a pre-ICS phone without installing GO.
Now, the GO Team has brought the goodness of GO Launcher EX to Android 3.0+ tablets by way of GO Launcher HD. It's still in beta at this point, though it doesn't quite have that "beta" feel to it; in fact, it already feels polished enough to use as a daily driver.
If you're familiar with GO Launcher EX, then you'll feel right at home in GO HD. It offers many of the same features as its phone-specific counterpart, albeit a bit stripped down (likely due to the fact that it's still beta) - you won't find any of the GO's typical flippy-floppy transition animations or the bells and whistles of EX, but we imagine they'll be present in the final version.
GO HD offers a few customizations to the homescreens right now, like the ability to modify the grid size. Otherwise, it's basically a standard launcher with a static dock bar at the bottom of all home screens. One great thing about this launcher in its current state is how intuitive it is. It all flows really well - everything from adding new items to the homescreens to changing settings just makes sense.
Since GO HD is still beta, it's not yet in the Market, so hit this link to grab the download and give it a shot.