Update guys:

I swapped in new spark plugs and have put about 10 miles on the car with mixed freeway/city/stoplight driving.

No issues...seems to be running well. I even drove it around, got it totally warm, cut it off for 15 minutes, and then fired it back up and drove it across the street for a quick errand.

Hopefully it was just the needle/seat. I still can't quite tell exactly what was "wrong" with the old set...maybe the o-ring on it is slightly shriveled but the needle itself looks ok.