Is the A77 meant to be a low ISO camera

I rented the A77 knowing it has noise at higher ISOs. Very impressed with the camera (I shot RAW), but it still surprises me how much noise there is at ISO 800 and up. Sony is known for their high performing sensors and other cameras, such as the Olympus E-M5, exhibit better high ISO performance. On the flip side it is astounding at low ISOs. With the EVF it is truly a great camera.

The high ISO noise is not enough to deter me (don't mind it as long as noise patterns are not "ugly," and the A77 still retains detail at higher ISOs), but I'm just wondering if the A77 is really optimized for and intended for low ISO usage, where it truly shines with wonderful dynamic range and clarity?

BTW I rented it with the 16-50/2.8 and was happy with that lens too! Only wish there was a fast 35mm-equiv 50mm lens available for it.