Retail means in a box, usually better, I don't know about OEm CPUs
So how do you know retail is better?
Retail, you get a nice shiny box, instructions, <b>drivers</b>, probably a bit of extra software and maybe a game demo or whatever on cd.
OEM, you get a box (if your lucky...), more than likely you get the component in a antistatic bag with the driver cd attatched with an elastic band, as for better or worse, I'd say it depends on where you buy it from more more than anything, Ive seen "companies" at computer fairs where motherboards etc are literally thrown in a box- obviously not the supplier to buy from, but I have also seen retail supplier replace a faulty item (MINE!- it was a faulty cd drive), replace it, and put the faulty one back on the shelf!!
I personally tend to buy OEM, maily because they are cheaper (cheap=good, free=better), I dont want crappy demo cd's and shiny boxes, and dont normally need instructions, I sometimes buy retail, depends on what I need and how quick I need it, but either way, I wouldnt say one is better than the other.
Next time you wave - use all your fingers