It's 419. (I'm here all week. Have you tried the fish?)
Are these the two?
319:
http://www.seatguru.com/airlines/Del...irbus_A319.php
738:
http://www.seatguru.com/airlines/Del..._737-800_A.php
The 738, versus the 73H, have overhead TVs rather than in-seat entertainment (see the 'video' details on the 738 link). Either way, it's better than the zero entertainment the 319s have.
And maybe this is just a personal thing, but the engines in the 319 seem very, very loud than what I experience on other planes. I cringe any time I have a flight coming up on one of these, and make double sure my noise cancelling headphones are fully charged.
I'd personally say you just experienced an equipment upgrade.
//A