Meredith Vieira appeared on “Today” Monday, which beat Katie Couric’s appearance on “GMA.” (NBC NewsWire/PETER KRAMER/NBC)

Monday’s “Today” averaged 4.9 million viewers, according to fast national ratings.

“GMA,” featuring the highly hyped return of former “Today” show sweetheart Couric, clocked nearly half a million fewer viewers.

The season to date gap between these two shows: 528,000 viewers.

(In the 25-54 age bracket – that’s the demographic news programs sell to advertisers — Monday’s “Today” posted 2.2 million viewers, which is about 444,000 better than “GMA,” according to those early stats.)

Monday is “Today’s” most watched day of the week, on average this season, though that probably has a lot to do with NBC having NFL football on Sunday nights in the fourth quarter. (The official broadcast TV season starts in mid-September).

Monday is also typically one of “GMA’s” lower rated mornings. “GMA” this season is doing its best numbers on Tuesdays and Wednesdays — the mornings after “Dancing with the Stars.”

Couric is co-anchoring “GMA” all this week while Robin Roberts takes a vacation. Couric’s getting ready to launch her syndicated daytime talk show in the fall; it’s being exec produced by her former “Today” show exec producer and distributed by ABC parent Disney.

After “GMA” announced its weeklong Couric booking, “Today” promoted some big “gets for the same week. Monday’s promised to be a “surprise legend” — who turned out to be NBC News correspondent Meredith Vieira announcing she would participate in NBC’s Olympic coverage of the Summer Games in London.

NBC noted Tuesday that “GMA” enjoyed bigger ratings two Mondays ago than it did this past Monday with Couric.

This is true: two Monday’s ago “GMA” averaged 4.974 million viewers.

Katie Couric, left, co-hosts with George Stephanopoulos on "GMA.” (Lou Rocco/AP)