Typical of the issues with streaming, MLB.tv's biggest issue has always been contractual: the service isn't terribly useful for its largest potential market, fans who want to watch their local team.
It took them years and years to even come up with the system they finally have now to allow you to pay extra to stream local games if you also already subscribe to the local team's cable/sat channel.
When you're actually allowed to access the content, it works like a dream.
If you've ever tried the NFL's streaming service ... it usually works, but rarely without regularly dropping down to miniscule, unwatchable bitrates.
Games regularly fail to load with the message "This game is not-yet available, check bat at time X" where X is several hours in the past. Complaining on twitter usually gets someone to fix those issues though (whatever you do don't try going through the "support" link, you'll get a response something like 2 days later).
It took them years and years to even come up with the system they finally have now to allow you to pay extra to stream local games if you also already subscribe to the local team's cable/sat channel.
When you're actually allowed to access the content, it works like a dream.