Sunjan, you always bring us the best recorder news!
The LS-7 is quite different than the LS-5 announced last Summer and sold in Europe. For example, the LS-7 weighs 90g including two AAA cells, while the LS-5 weighs 165g. I wonder if this means the LS-7 has a plastic case. The LS-5, LS-10 and LS-11 have a metal case.
Also different: The LS-7 supplements the L&R mics with a center microphone. There is no center mic in the LS-5, or in the more expensive LS-10 and LS-11 models. Specs listed above say low frequency response is improved with center mic (sensitive to sounds as low as 20 Hz, instead of 70 Hz with center mic turned off). The text implies that the center mic works with the L&R mics, rather than turning them off when the center speaker is on.
The LS-7 has a single speaker, while the LS-5, LS-10 and LS-11 have a pair of speakers. The LS-7 uses MicroSD card, while the others use SD or SDHC.
Let's hope that the street price of this model falls quickly. The LS-11 costs about $235 these days, and it has 8 GB of internal memory rather than 4GB like the LS-7. I'm guessing the LS-7 will have a street price of $169 initially, and then fall to $150 or so by Summer. That puts the LS-7 between the Tascam DR-8 and DR-2D models.
[update: the body of the LS-7 is "ightweight aluminum," according to Olympus. ]