I'm not sure it will be Robinson.
I think it depends on the criteria people voted on. Personally I voted it first, and furthermore it was the only moment I voted for that technically can't be memorable for me (I wasn't born and I certainly didn't follow baseball).
However, I think Robinson's rookie year is something that transcends the sport, and thus to call it MLB's most memorable moment may not be entirely accurate. I would guess many people voted for something that is clearly a
baseball moment, like Maz's homer, McGwire and Sosa's 1998 or DiMaggio's streak. I can see why many people would see what Robinson did as having social and political significance far ahead of its baseball impact and thus feel it's not really suitable as a Major League Baseball memorable moment.
I guess i'm coming from an antithetical point of view here, that is i'd like Robinson to take the most memorable moment but i'm really not sure he will. I think McGwire and Sosa will definitely rank pretty high as will Mazeroski and Ted Williams (the tributes after his passing earlier this year should've served to elevate that a fair bit in people's minds).
And if you want a dead certainty, Carl Hubbell's All-Star game will be nowhere to be seen
