commodity ETF questions

[joesxm]

I searched the forum using google and saw some posts from a year or two ago that were recommending PCRIX, DJP and DBC as ways of getting a commodity exposure in your asset allocation.

Are these still the good ones or have new ETF's come out since then?

I saw the DJP is an exchange traded note so it is tax-wise better in taxable account.

Given the run up in commodities is it a bad time to be buying some? Should I wait until they hopefully drop sometime in the next few years?

I intend to increase my REIT allocation by buying more VNQ and bought about 1/3 of what I plan to today. Any thoughts on the timing? I am assuming that if I want REIT for the long term now is a better time to be buying REIT than commodities if you believe in the buy sort of near the bottom philosophy.

Thanks in advance for the advice.