This gets asked all the time, and no one knows. Apple is very secretive about its release schedules of new products. Anyone who does know would be risking their job to tell anyone.
Usually the MBP line gets updated 3X/year, but the last update was around the middle of last year, so odds are the new update will be in Q1 of this year. Of course that means anytime between now about about March or April. USUALLY releases will be announced at some big event, but then you have things like the redesigned Mac Mini release which caught everyone by surprise. So the exact date is anyone's guess.
Also, just because it's a newer refresh doesn't always mean it's a better product. Just about everything from the Mid-2007 refresh era was a piece of garbage. A lot of the early MBPs had problematic nVidia graphics chips. The Early 09 Mac Pros had issues early on that were eventually fixed with firmware updates. Apple refreshes products more because there's some financial advantage for them to do so. The new design might be cheaper to build because it uses fewer components or something along those lines. It isn't because it's a necessarily superior machine from the consumer's perspective. Removing the HDD from the latest AppleTV refresh would be considered a significant step backwards by many.
I heard the Apple company is doing the periodic upgrading like they just did with the iPods (I never had an iPod but I invested in a new Nano, and I have no idea why you can't turn it off, but that is another topic.) Anybody have any idea when a good time is for a new MBP, besides "when you need one."
I would like to get one when they have just reviewed and overhauled the MBP like they just did with the MB Air.
thanks.

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