I believe so...On my Roku I saw the banner saying it was available.
And I got this in my email:
The MLB.TV channel will appear on your Roku automatically soon. If you’re excited to get started right away, you can access a pre-release version now. Note that you might see intermittent playback errors on this version.
1. From the Roku home screen, select the “Settings” icon.
2. Select the “Player Info” icon within “Settings.”
3. Select “Check for Update.”
4. Confirm that you want to update your player.*
5. Once your player has been updated, select “OK” to restart the player.
* There is a possibility that the Roku player will state it has the most up to date software already installed. If this happens, just try updating again, and it will begin the update process.
If you haven’t yet signed up for MLB.TV®, buy a subscription now. If you have feedback on the pre-release MLB.TV channel, please send it to mlb@roku.com.
