Waiting time on the Pen E-P4

I've been shooting on a full frame DSLR for years, but recently a friend leant me his EM-5 and I'm kind of hooked on the idea of not carrying around a gigantic kit...

I've done a little research and I really like the E-P3 for its small size, controls, and good looks... I'd like to wait until they release the E-P4 though before purchasing (I'm hoping it hosts a new sensor that handles better at high ISO and overal IQ)... I've heard that it's rumored to be announced some time in September, but I'm wondering if any of you have any insite as to what the normal waiting time is on Olympus cameras... In the Canon/Nikon SLR world, it can take months to get a new model camera (People are still having a hard time purchasing the D800/D4, and 5DMKII/1DX due to high demands)...

I have a trip to Argentina in January and I'd hate to preorder the E-P4, only to receive it months after my trip... I know that the availability of the EM-5 is still a little up in the air (on backorder most places). Does anyone expect the same thing to happen for the E-P4?

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