We reported over a week ago now, that Honeycomb 3.1 is available for the limited edition version of the Samsung Galaxy Tab 10.1, given away at Google IO. Today Google sent an email to those lucky owners officially letting them know of the upgrade, as well as some instructions for the download. The 3.1 upgrade brings some nice updates to the tablet version of Android, so if you haven’t gotten the update yet for your IO Tab, check your inbox.

The Galaxy Tab may have just come out last week, but the lucky attendees of Google’s IO conference in May have been playing with their limited edition versions of the tablet since then. Since the retail version of Samsung’s new tablet launched with 3.1, it only made sense that the IO version would get it as well.

The update brings some handy new features, chief among them re-sizable widgets, improved multi-tasking, and USB hosting. Among these exciting new toys, USB hosting requires a USB adapter for the Galaxy Tab, which uses a 30-pin adapter. Since USB hosting is fairly new, Google obviously wants developers coming up with exciting new ways to use it. As such, they’re offering IO attendees a discount on Samsung’s 30-pin to USB adapter with a discount code included in the email.

If you haven’t downloaded the update yet, then Google gives you the following instructions:

1. Prepare Your Device

Before starting the update, ensure that your tablet’s battery is fully charged. When the battery is charged, disconnect the charger from the device. During the update, do not connect the charger to your device.
Ensure that the tablet has network access over a Wi-Fi connection.
Ensure that you are currently signed in to your Google account in Settings > Accounts & Sync.
If you encrypted your tablet (through Settings > Location & Security > Encryption), please note that you must disable decryption and perform a factory reset of the device before continuing. The factory reset will erase all data on the device. For automated backup and restore for your Google account, you can enable Settings > Privacy > Backup and restore. To reset your device, use Settings > Privacy > Personal data > Factory data reset.
2. Set up a Samsung account

To receive the Android 3.1 update, you need to set up a Samsung account to register your device. You can set up the account using Settings > Accounts & Sync > Add Account > Samsung account.
If you already have a Samsung account, sign in to the account before continuing.
3. Download and install the update

To download and install the update use Settings > About Tablet > Software update.
Use the on-screen dialogs to accept the download, install the update, and reboot the device.

The update should preserve all of your files, but as always, its better to be safe than sorry. The other issue to note, is that the update does require you to re-root your tablet if you had already done so. Other than those two warnings, go ahead and set up that Samsung account and download the update. After using 3.1 for a week, the improved task switching is a god-send, and the re-sizable widgets makes popular widgets like GMail’s much more usable on the homescreen, and as soon as I can get my hands on that adapter I’ll let you know how USB hosting is too.