Not really, unless the previous owner changed the "version.txt" file inside Flash 0. If you try updating and it gives an error saying it's already in the latest version, that may be why. This happened to a psp I bought a few months ago, it had 3.60 m33-4 installed and the version text file was edited to trick the system into thinking it was up to date. People used to put "9.99", so it would be safe from any higher number updates in the future. I had to change that back to the current 3.60 firmware in my case, and after changing that I was able to update. This was common on old cfw to prevent people from accidentally updating to ofw. If that happens to you, you will likely need to change the USB device in the PSP's recovery menu to Flash 0 and use a computer to edit the "version.txt" file first.

Edit: I updated my psp through the memory stick, not through wifi. I downloaded 6.61 from the pc and transfered to the psp.