The reg was part of the 135 changes that went through with Part 91, Subpart K (Fractional Ownership). The new reg basically says you can go into an airport without weather reporting provided you can obtain a local altimeter setting and you are a "qualified" air carrier. I forget the actual terminology, but there is a list of criteria (two pilots, certain equipment, etc). Do a search on subpart K, I know there was a lot of discussion of the qualifications as many thought they were new requirements for all 135 aircraft (but they are not). As far as I know, this will not be included in any Ops Specs as it is an FAR, but they may update the current approved weather sources Ops Specs.
While on the subject, has anybody seen any criteria in order to use the new regs allowing for short runways under 135 (80% rule vs. 60% rule). I know you must have an airport performance program, but I haven't seen any guidance. I have been told that this will not be a study as required by 121 ops, but instead an approved program that your pilots will follow in determining aircraft performance at a specific airport with specific conditions. Just curious.