I had my interview at the Dallas DO today May 14th. It went very well. I was very nervous about my extensive travel over the past 5 years. I had some 800 odd days of travel that included trips to a lot of countries in the world. But none of my trips was over 6 months, the maximum trip length was 110 days. I was working for a US company as a contractor and did have a letter from the company for the reason for the numerous visits.
N-400 timeline (2013):
SC: Texas
USCIS: NYC
April:
22 : Application Filed
24 : USCIS Received Date
24 : Priority Date
26 : NOA - (I-797C)
29 : Check Cashed
May:
02 : FP Notice Received
29 : FP Done
31 : In-line for Interview
August:
06 : NOA - interview scheduled
08 : YL received
10 : Interview letter received
September:
10 : Interview - passed
11 : NOA - Oath letter sent
16 : Oath letter received
October:
04 : Oath