Found a way on Windows!
With the help of the vendor ID from above and the following article on generic Tegra Tablets, was able to get it to show up on Windows!
(Copied from addictivetips)
1.You must have Android SDK installed before you can proceed. If you don’t have it already, proceed to our guide on what is ADB and how to install it. Make sure you download the Google USB Driver Package as well.
2.Open the google-usb_driver folder that you will find inside your Android SDK folder.
3.Open the android_winusb.inf file in notepad or any text editor to edit it.
4.Add these lines under [Google.NTx86] or [Google.NTamd64] depending on whether you are using 32 bit or 64 bit Windows. If unsure, it is safe to add these under both these sections. ;NVIDIA Tegra
%SingleAdbInterface% = USB_Install, USB\VID_0955&PID_7000
%CompositeAdbInterface% = USB_Install, USB\VID_0955&PID_7100&MI_01
Don’t edit or replace any other text that is already there; just add these new lines and save the file.
5.Open a command prompt window and enter this command: echo 0x054C >> "%USERPROFILE%\.android\adb_usb.ini"
Note: this is where you have to use 0x054C instead of what is at the link, otherwise it wont work
Now your Android SDK drivers are configured to support any Nvidia Tegra based tablet. To be able to use ADB and other SDK tools with your device, you can proceed as follows:
1.On your tablet, go to Menu > Settings > Applications > Development and enable ‘USB Debugging’.
2.Connect your tablet to your PC via USB. You will get a notification that some drivers were not installed, which is OK for now.
3.Right-click ‘Computer’ and click ‘Manage’. Identify your device from the list, right-click it and click ‘Update Driver Software..’.
4.Choose to browse your computer for driver software and then select to pick from a list device drivers on your computer.
5.Choose to view all devices and click ‘Have Disk…’.
6.Browse to the google-usb_driver folder inside your Android SDK folder and select the android_winusb.inf file.
7.If you get any warnings prompts telling you that the driver might not be compatible, just choose to continue installing.
8.Once the drivers have been installed, you should be able to use ADB with your device.
9.To confirm that your device is recognized, launch a Command Prompt window and enter these commands: adb kill-server
adb start-server
adb devices
Also, using BRKs Transformer's instructions found a way to boot Tablet S into recovery: has reboot, update from ZIP and factory reset options
a) Hold down power and volume UP button
b) when SONY logo appears, release power button but keep pressing volume UP button
c) should load into recovery
This also gives us the MTP device driver, which I have been unable in finding/installing
No luck so far with Automated rooting tools, working hard to crack this awesome tablet!