Should I put money in my 401 or IRA?

This is one of the very often asked questions on both mimf and mifp.
Based on comments on both newsgroups, here is what seems to make most sense:

1. Contribute to your 401 upto your employers match (employer match is free money)
2. Invest in IRA upto the maximum limit (because IRA gives more options than 401)
3. Invest in 401 upto the maximum limit