A letter posted on Eric Alterman's blog (MSNBC - Altercation) points out that we're seeing wall-to-wall coverage of the Reagan laying in state event, which they estimate will draw about 200,000 people.
In contrast, six weeks ago the March for Women's Lives, the pro-choice protest march in Washington, D.C. that drew over 870,000 (a conservative estimate) and is believed to be one of the largest marches ever held in the nation's capitol, received little more than a few seconds footage on the evening news.
(As an example, I went to the CNN archives to verify numbers and found exactly zero stories reporting the march. I did find one story from The Morning Grind, written the week before the march, that evaluated political aspects of the event, and one other story reporting on outrage to Karen Hughes' comment that the protesters were terrorists. Nothing on the march. Zip. Zero. Nice, huh?)