The core complaint revolves around bad controls:
http://www.eurogamer.net/articles/ea-sports-grand-slam-tennis-review
So the question in my mind, especially given the 75 and 90 scores I've seen other reviewers give this game, is whether this game is actually hard to control, or if the reviewer just sucks at motion controls. We've seen a lot of reviews this generation which boil down to, "I don't know how to operate this white chunk of plastic." WM+ might end up ushering in a whole new wave of such reviews.
"The worst part about these reviews is they are [subjective]--and their scores often depend on how drunk you got the media at a Street Fighter event." — Mona Hamilton, Capcom Senior VP of Marketing
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