A big push by big-box stores and online retailers to bring Black Friday to the web -- and to do so earlier than ever -- seems to have paid off this year.

Online sales were up 39.3% on Thanksgiving Day and 24.3% on Black Friday compared to the same days last year, according to IBM's (IBM, Fortune 500) Coremetrics, which tracks real-time data from 500 retailers in the apparel, department store, health and beauty and home goods categories.