Harvard scientists predict the future of the past tense

"Lieberman and Michel's group computed the "half-lives" of the surviving irregular verbs to predict how long they will take to regularize. The most common ones, such as "be" and "think," have such long half-lives (38,800 years and 14,400 years, respectively) that they will effectively never become regular. Irregular verbs with lower frequencies of use -- such as "shrive" and "smite," with half-lives of 300 and 700 years, respectively -- are much more likely to succumb to regularization."

http://www.sciencecodex.com/harvard_scientists_predict_the_future_of_the_past_tense