Well, yes, technically it is. Sending something to your email inbox is not a "publication," and there's no direct way for me to access your email inbox. Now, personally I've used email queries to get facts straight, and have sometimes quoted these emails (with permission) on talk pages. For example, it wasn't too clear from published sources whether the Babson Globe on the Babson College campus in Needham does or does not rotate _as of 2006_, and I queried Babson to resolve the ambiguity; see http://en.wikipedia.org/wiki/ Talk:Babson_College#Phrasing_claim_for_the_Babson_Globe This has held up mostly because not many people care deeply about the fact, and other editors have been willing to accept this. It wouldn't hold up against an editor that seriously challenged it.