Remember Nascar is on what, every Sunday like football? I don't watch it. And Baseball has how many games played each and every day? The transponder space for Nascar is minimal and only for hours each week. The transponder space for MLB is massive.
I for one hope they do not add EI. I like baseball, but love football, and I would not subscribe to NFL sunday ticket as watching non-HD sports is garbage. So unless they were going to add something like 10-HD MLB channels I can't see it.
Now if they can free up transponder space or get on a third bird - then it should be added (if enough people would subscribe)