It DOES work from the stock browser. Unlike the Wintel PC version, you don't get the NEXDEF enabled features like jump to inning, etc. It should get better when flash player gets updated to enable Tegra hardware acceleration. A dedicated MLB app would also presumably add a better user interface and maybe optimized streaming. Some of the flash menus in the browser window are kind of hard to work with a fat finger rather than a mouse. Like any MLB-TV installation, you will need a fast wifi network connection to get usable streaming. I'm watching a game right now on a so-so wifi connection and it's maintaining pretty chop-free standard def streaming. With the current version of flash, it will work better if you run the player full-screen. If it ever warms up, I can see it now...beer, backyard, baseball on the Xoom...
Cheers.