On one hand, with Main Street representing Walt's idyllic memories of his childhood in Marceline and the ideal of the American small hometown, there is a certain symmetry in the idea that Buena Vista Street would represent the excitement of his arrival in Los Angeles as a young man, and the general idea of coming to California/"the big city" to "make it."
On the other hand, I'm glad it's going to be called Buena Vista Street instead of Walt Disney Plaza, as I read at one point (or is part of the street still called Walt Disney Plaza?) That did seem rather like sticking his name on there to say to the purists - "Look, the park has Walt in it now! It's even got his name!" Which of course, like slapping familiar Disney characters on a ride to make it "more Disney," would be entirely missing the point.
If Walt is now being treated like "another character," at least he's a character who actually did spend a lot of time in California, unlike many of the fictitious ones they're using!