Every day we get asked a variation of these questions: "Is this show canceled?" "Is that show coming back?" And as the five broadcast networks (ABC, Fox, NBC, CBS and The CW) look toward their new crop of pilots, these are valid concerns.Some shows have already been visited by the cancellation grim reaper (we already forgot you, "Work It"); others, like "How I Met Your Mother," have been renewed; some are as good as renewed (like "Glee," for better or for worse); and then there are the rest, like "Community," that find themselves positioned on the dreaded bubble.