Capacitor type for AD8307 NP0? X7R?

Where in the datasheet do you see a recommendation to use NPO caps on the inputs?

I dont see a recommendation for that. Why would you not use NP0 there though? Since that is a RF input, you would think you wouldn't want the front end to be drifting up and down, or drifting  unequally with temperature? 

I only mentioned NPO caps in response to your original question. I looked up the documentation for the AD8307 evaluation board and see that the two input caps are ceramic capacitors (part number 06033A102JAT2A from KYOCERA AVX). I also had a look at the AD8310 evaluation board (very similar part). It uses Kemet C0603C103K1RACAUTO which is also a ceramic cap. So I would recommend something like those.  
For operation at low frequencies, tantalum electrolytics are recommended (see section  on page 22 of the datasheet). The choice for the cap that you connect to the OFS pin (if you are using the OFS function), is not critical as this is a low frequency node.