The "to" addresses probably don't tell you much. I've received emails that are sent cc'd to all the winners if there are more than one (not the ideal email practice, but a lot of people don't follow the ideal email practices).
who is it from? if there's a something.com in the sender's email address that isn't yahoo/hotmail/gmail/other generic? do a search for that URL Is it from a generic ID, or an individual?
Since they are open to questions, I'd send an email back asking which sweepstakes it's for before I'd fill out an affy. If you don't get a relatively prompt response, then let it go and move on.
And, most importantly, did you enter any sweeps with a $20 Walmart GC as the prize? you can search on that on sweepsadvantage.
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I just reread (missed the first line that it was from Big Prize Giveaways, but saw the BPG sign-off). That means it's one you entered on Facebook. I'd still send an email back asking some questions about which sweep and I'd take a look at how much info they want on the affy. (Is it like the SheKnows affy where it just formalizes the info you would normally send in an email, or do they want the whole SSN/notarized deal?)
Most excellent response! I added it to our stickied thread:
weird winning email notifications to look for http://www.sweepstakesplus.com/smf/weird-winning-email-notifications-to-look-for-t24913.0.html
