With comings and goings on the network morning shows on the horizon, all three broadcasts saw a big year-over-year increases last week, due to the news of the killing of Osama Bin Laden.

“Good Morning America” had its most-watched Monday telecast in more than 5 years last week with Diane Sawyer joining the “GMA” team (after having its best Friday telecast the week prior — Royal Wedding day — in 6 years ). NBC’s “Today” still reigns winning in all measurements and having its best A25-54 gap over #2 “GMA” in eight weeks. Season to date, “Today” is up +5% in the demo. “GMA” and “The Early Show” are flat.

In Total Viewers, season to date “GMA” is up the most (+8%) compared to its year-ago average. “Early Show” is up +2% and “Today” is down -1%.

Compared to the same week last year, “Today” added about a half million viewers, “GMA” added just shy of 600,000 and “Early” garnered 200,000 more than the same week in 2010.

The averages for the week of May 2:

• Total Viewers: NBC: 5.96M / ABC: 5.14M / CBS: 2.68M

• A25-54 viewers: NBC: 2.75M / ABC: 1.96M / CBS: 1.10K