It depends on what you are going to be using it for. If you are putting one over a bait source I would say the Stealth I590 for around $100 is the best bang for the buck right now. I seems to have a better sensor than the D40 does and takes higher quality pictures and records the temperature and moon phase on the photo all for about $10 more than the D40. If you want an all around camera that will also be useful on trails I would recommend the Scoutguard 550 at around $200.

I've personally used 2 different models of Moultries (3 different cameras), 2 different models of Stealthcams (4 different cameras), a Bushnelland a Scoutguard. I keep my cameras out 24/7/365 so things like battery life and durability are important to me.

If you really want to know and hear about folks that have a passion for trail cameras, check out www.chasingame.com the entire site is dedicated to trail cameras.