Hypochlorhydria (low stomach acid) could be an issue. Lack of proper stomach acid will lead to lack of absorption of B12 through intrinsic factor activation as well as poor digestion of the meat where you would get the iron from. That being said, with most people I see on good diets like you are on, any anemia is usually corrected barring other problems. Hence my concern about lead.
Scott, for you and anyone else interested, if you want to know what metals could be problems in your area or in areas you may have lived previously, see
http://www.scorecard.org/. Specific section on lead here:
http://www.scorecard.org/env-releases/lead/.
For more on lead and anemia, here's a couple of studies I found, you're welcome to decide whether they are potentially applicable in your situation or not.
Blood lead and hemoglobin levels in Andean children with chronic lead intoxication.
Should all patients with unexplained anaemia be screened for chronic lead poisoning?
When I've tested patients for toxic metals who have amalgam/mercury fillings, I nearly always find elevated lead (along with mercury). FWIW. Note that this is not the conventional blood test (which tends to miss chronic toxicity), it is a multi-hour urine test.