A VFR Europa and a Beech Baron had a near miss as the Europa descended through 2700 FT on the edge of Class D to its home field and the Beech was passing through the adjacent Class D at 2600 FT.

Narrative

On a CAVU afternoon while returning to my home field; I passed several hundred FT above the 3;000 FT top of ZZZ Class D airspace and commenced a gradual descent; planning to just clear the Class D as I passed its northeast edge. In the vicinity of the airspace boundary I was surprised by a twin Baron at 10 o'clock position about a half mile and slightly below me but approaching head-on. I stopped my descent and the Baron passed below me about 100-200 FT. Upon landing at my home field; I was directed to call ZZZ Tower. ZZZ ATCT stated that it appeared that I had clipped the top of their Class D while they had traffic passing through their airspace just 2 miles north at 2;600 FT. ZZZ had been receiving my Mode C intermittently so they were not sure of my altitude. Lesson learned: Particularly in metropolitan airspace; don't fly close outside the edge of Class BCD airspace because that is where aircraft avoiding entry often fly. Or perhaps the better course of action would be to fly through the airspace (with clearance) and with Controller communications.