Depending on whom you ask, U.S. online shopping is either in unprecedented decline – or one of the only bright spots in American retail.

On Thursday, comScore reported that U.S. online spending in the third quarter slipped 2% to $29.6 billion versus last year. That represents the first time since comScore began tracking the figures that online spending has shrunk for two quarters in a row. (Online shopping was flat in the first quarter, and slipped 1% in the second quarter.) ComScore was slightly more upbeat about the potential of growth in the fourth quarter, if only because we’ll be comparing it to last year’s dismal fourth quarter.

But on Monday, Forrester Research put out a report that reached a different conclusion: online sales in November and December are likely to grow 8% compared to last year. Moreover, a survey Forrester conducted with the National Retail Foundation found that online retailers reported sales in the third quarter grew 16%.

Who’s right?

Both firms look at online shopping excluding areas such as travel and car purchases. But the two take