This is why checking the fees of the products you buy when you invest is so important. I'm lucky enough to have index fund options at 0.04% and bond fund options at 0.07% in my 401k. That doesn't matter if you don't use them though! I work with some pretty smart people that used to put their 401ks in target funds with fees in excess of 2.0% until I sat them down and worked out the math with them.

If you want to quickly eyeball how your 401k stacks up, Brightscope (http://www.brightscope.com/) is pretty useful.