@Stan McStanly Tennis might actually be a bit less predictable than in Wii Sports. Applying spin works really well, but the differentiation between forehands and backhands leads to the occasional shank. Especially at the net.
Also, I still can't reliably aim my spikes in volleyball. But badminton recognizes which side you want to hit it toward fairly accurately. Superficially, tennis and badminton are similar, but the motion recognition is completely different.