This new Lexus Europe video of the 2013 RX 450h is packed with previously unseen footage:
It was mentioned in the comments a couple days back, but this video confirms that the RX drive mode selection (Normal, Sport) is controlled through the steering wheel — here’s a zoomed-in look at the buttons:

As there doesn’t appear to be a dedicated button, it looks as though the Sport mode is accessed through the information display in the instrument panel, similar to the current RX’s ECO mode selection.
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