It remains very early in the game, and there is still tremendous room for consumer usage and category growth by multiple players in this space.

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Panera: One might have thought there was no room left in the fast food category, let alone new thoughts to think about the category, that is until Panera came along.

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With HP's primary play in webOS being outside the smartphone market, it creates more room to license webOS in that high-volume category --a place where the OS really needs to attract developers.

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Perhaps the most surprising budget black holes are room fragrances and candles, now a multi-billion dollar category.

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Mr. Frija: Right now, this category is growing so fast I think there is room for lots of companies to expand and have a chance to achieve profitability.

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Indeed, almost every category of costly medical care went down: doctor visits, emergency-room and hospital visits, drug prescriptions.

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