We were on the Maiden Voyage (12-26JAN) which did cross the Atlantic, (quite splendidly I might add!) There are two reasons that the recent crossing was also a 'maiden'
1. To many, the maiden transatlantic voyage doesn't occur unless it's a nonstop from Europe to N. America...some purists would even go and say it must end in NY.
2. Marketing! As you say, Cunard could have 'maidens' for 20 years.
I still say we were on the maiden voyage and maiden transatlantic all rolled into one! :-)