I also had this issue.
I installed the new Google Music Beta program from the Android Market and set up Google Music to upload my songs from the PC. I would not see anything on my Xoom.
Here's how I fixed it and now Google Music works great for me.
1. Make sure that the google account is set to the account you signed with for Google Music Beta
a) Go into Google Music Beta and at the top right corner there are 4 horizontal bars. Click that
b) A menu opens up, click on Settings
c) The first field: Google Account, make sure it is the account you signed up with
2. Quit the Application and restart it. If this still has not fixed it (it did not fix it for me) proceed to do the followinng.
3. Go to Settings -> Applications -> Manage Applications -> Downloaded
4. Click on the "Music" Program
5. Click "Force Stop"
6. Click "Clear Data"
The steps above will force the program to reset itself. The next time you start the program up it will prompt to begin with your Google Account.
7. Start the Google Music Beta application again. It will prompt you to use one of your Google Accounts, choose the account you signed up for Google Music Beta with.
8. That is it. You are done. Google Music Beta should now work.
Hopefully this is helpful to all of you. As I mentioned, I did this and I now have a working Google Music Beta. It's great!
---------------------------
Other things to try if it still does not work.
1. Go to Settings -> Accounts & Sync and choose the account you are using for Google Music Beta. Prompt to re-sync this account.
2. Uninstall the updates to the Google Music application, then reinstall. The program should now prompt you for your Google Music Beta account upon starting
I installed the new Google Music Beta program from the Android Market and set up Google Music to upload my songs from the PC. I would not see anything on my Xoom.
Here's how I fixed it and now Google Music works great for me.
1. Make sure that the google account is set to the account you signed with for Google Music Beta
a) Go into Google Music Beta and at the top right corner there are 4 horizontal bars. Click that
b) A menu opens up, click on Settings
c) The first field: Google Account, make sure it is the account you signed up with
2. Quit the Application and restart it. If this still has not fixed it (it did not fix it for me) proceed to do the followinng.
3. Go to Settings -> Applications -> Manage Applications -> Downloaded
4. Click on the "Music" Program
5. Click "Force Stop"
6. Click "Clear Data"
The steps above will force the program to reset itself. The next time you start the program up it will prompt to begin with your Google Account.
7. Start the Google Music Beta application again. It will prompt you to use one of your Google Accounts, choose the account you signed up for Google Music Beta with.
8. That is it. You are done. Google Music Beta should now work.
Hopefully this is helpful to all of you. As I mentioned, I did this and I now have a working Google Music Beta. It's great!
---------------------------
Other things to try if it still does not work.
1. Go to Settings -> Accounts & Sync and choose the account you are using for Google Music Beta. Prompt to re-sync this account.
2. Uninstall the updates to the Google Music application, then reinstall. The program should now prompt you for your Google Music Beta account upon starting