The end of multi-aspect ratio sensors?

The new GH3 has a 4:3 sensor cropped in the usual way for other shapes, rather than then wider sensors of the GH1 and GH2. Stranger is the fact that the G5 also does not offer the multi-aspect ratio feature, but some specs (the 18MP total pixel count) suggest that it has a wider sensor but is not using the extra width for its 3:2 and 16:9 output.

What is going on?

One guess is a copy-and-paste error in the G5 spec sheet, with that sensor being in the usual 4:3 shape as its output options suggest. In fact, the G5 and GH3 could be using the same sensor, just with different processing behind them like slightly different minimum ISO speed options.

In any case, it seems that Panasonic has abandoned the wider multi-aspect ratio sensor idea.

A question to GH2 owners: do raw files contain all the extra pixels, or just the ones for the chosen crop? (EM5 raw files for shapes like 16:9 still have all the pixels, with a "flag" indicating the chosen crop.)

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Smaller lenses, better in low light, more telephoto reach:
you can have any two at one time.