Well I'm working on giving up dairy which is flipping hard. I only have milk to cook with for Christmas but I've stopped having cereal and ice cream and milkshakes and such. I plan to go off it completely in the new year and hopefully stick to almond milk or just find new recipes that don't need milk.
I'm also considering a gluten-free diet but I blame being old as hell for that
I could never be a vegan though, although I'm pretty much a chickentarian (or however its spelt) as I've pretty much given up red meat. I have issues with seafood due to taste and due to mercury issues.
I'm also planning to drop to around 1000-1200 calories a day for the new year because I'm tired of being heavy again after losing 80 pounds in 2009 (it's been 4 years but I've put all the weight I lost back on).