I've knit over half the length to the under arm, which is where you join the sleeves and things get exciting again. I'm really happy with the progess I'm making, I knit on this a little bit each day. Making hats in between has definitely helped with little bursts of instant gratification.
It's been tough working this 51" sweater on a 40" circular needle, but all is well now that I've gotten my new 47" cable from Knit Picks. Oddly enough, it came with 10 skeins of yarn as packing material. Weird.