Jessica’s Answer:

Here’s the Wikipedia description of the upfront: http://en.wikipedia.org/wiki/Upfront
In the North American television industry, an upfront is a meeting of television network executives with the press and, more important, with major advertisers. It is so called because it signals the start of an important advertising sales period, allowing marketers to buy commercial airtime “up front”, or several months before the season begins.
In the United States, the major broadcast networks’ upfronts occur in New York City during the third week of May, the last full week of that month’s sweeps period. The networks announce their fall primetime schedules, including tentative launch dates (i.e. fall or midseason) for new programming, which may be “picked up” the week before. The programming announcements themselves are usually augmented with clips from the new series, extravagant musical numbers, comedic scenes, and appearances by network stars, and take place at grand venues such as Radio City Music Hall or Carnegie Hall. Most cable networks present earlier in the spring since they usually program for the summer months; press attention to these announcements is usually much lighter.

Of course, now it’s June, so here’s what’s important to know once the shows have been picked up:
1. Soon after writers and crew are hired
2. As the writing staff are working, it’s a good time for actors to be planning their strategies for episodic work
3. Executives are VERY busy getting everything lined up- not a good time to be asking them for their time

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To your success!