RealTemp 3.70 should be reading Ivy Bridge CPUs correctly but I don't have an Ivy CPU to confirm this and most
of the people that do have Ivy CPUs are not talking.
From what I understand, the temperature data is still in the same register as previous Core 2 and Core i generations and the TJ Target or TJ Max register is also still in the same location as before so RealTemp and other monitoring applications should work as is.
There is a rumor that Ivy ES processors have TJ Target set to 91. Here is the formula that all software uses.
Reported Temperature = TJ Target - Digital Sensor Reading
All software assumes that the TJ Target value written to each CPU core is the same as actual TJ Max but the two values might not be the same. Intel has previously stated that actual TJ Max might be higher. Actual TJ Max might be 91, 98 or 100, 105 or some number in between. It might be consistent for all cores or it might be completely different from core to core. No one knows and the few people inside Intel that do know are not talking.
If there is a pile of unknown error in the TJ Target / TJ Max value and the sensors are far from 100% accurate from idle to full load then reported temperatures are more like random numbers.
I have read some forums where all sorts of conclusions are being drawn on how hot Ivy Bridge runs. That's nonsense. These conclusions are based on temperature data that can not be relied on for any of Intel's recent CPUs. Temperature data from Intel CPUs should not be compared to other CPUs in the same CPU family let alone comparisons to CPUs from different families.
RealTemp is a good program and the sensors are useful enough so that if you swap a heatsink you can see if things are better or worse but beyond that, Intel's core temperature sensors are not accurate enough or documented well enough to provide users with 100% accurate core temperatures.