First of all, while you likely have already, I suggest that you should review this and associated pages again: Facts about The New Security Research Findings and Intel Products. At the bottom, it includes a list of the affected processor families. All second and third generation Intel Core and Xeon processor are included.
Secondly, Intel's commitment is to have microcode updates available for all affected processors by the end of the month. Any concerns regarding missing microcode before the end of the month are premature and a waste of everyone's time. If you do not see the necessary updates at the end of the month, feel free to yell and scream then...
This message was posted on behalf of Intel Corporation
I understand you are looking for new Linux microcode for your Intel® processors. Let me help you on this matter.
It’s possible that some microcode updates will not be included in the download. Some microcode patches can only be delivered via BIOS update, that is why we recommend checking directly with your system manufacturer and OS provided updates.