I have a thing for a full qwerty (physical) keyboard so I would either go with the Curve or wait for the Niagra. Of Course I would keep up with Storm updates.
I got the Curve 5 months ago and I'm pretty happy with. I played with the Storm wasn't that impressed but I do want to mess around with it after this update since it sounds alot better.
If you really want the Storm I would hold off and see how the OS updates go.
Just my opinion this is all up to you after all
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