Durf sent along an interesting post about お陰様で on Japan Echo by a Japanese columnist. He notes that お陰様で has been used frequently in the areas affected by the earthquake and tsunami. The examples show how it’s really just an idiomatic greeting that can be used to acknowledge someone’s concern for your person. Most excellent. Start using it…now.
I was curious to see that the writer’s wife, a Kansai native, was unfamiliar with the term. My friend who just had a baby is from Sendai, but I can’t remember where my Japanese teacher is from. For the most part they tried to teach us 標準語 (ひょうじゅんご), so I’m tempted to say that お陰様で works in the capital as well.