How about we split the difference on who's right. ;-) The problem is that "Old Siri" no longer exists, and no longer operates on any iPhones (not updated after acquisition, removed as of Oct '11).
"Apple Siri" (initially released Aug '11) is for all intents and purposes a different product - sold by a different company, works on a different set of phones, is a different type of product (integrated vs. independent app), ,operates better, and marketed a gazillion times better. If they left "Old Siri" in older versions of iOS I'd agree with you, but this is a distinctly different product. It's like saying Microsoft Surface has actually been out since 2008 - while technically accurate, they were selling tables the last few years, not tablets.
OTOH Voice Actions (always by Google) never went away, and continues to work on all phones (2.2 and on) that could support it. Don't need any crazy semantic discussion to understand that :-P