I know this is possibly beating a totally dead horse, and if anyone's paying attention then great! but with "text" being synonymous with "text message" and "texting" being synonymous with "text messaging" as in, the act of sending a text message, I propose that the past tense is indeed texted. Because you don't "text message" someone yesterday, you "text messaged". "texted" is simply a contraction of "text messaged."