For reference, here's some prompting questions that are showing up in my social media streams. These change from time to time as online sites try to cajole, coerce, trigger or prompt people to participate online.
Typepad wants me to share this post, and to "Enter a short message about your blog post to get people excited to come read it."
Facebook is asking me "What's the best thing that's happened to you today?" I'm sure that this is not the only question that Facebook asks, based on other people's reports, but I haven't yet seen a comprehensive list of the prompts.
Twitter is asking me to "Compose new Tweet…"
And Google's Gmail is just directing me to "COMPOSE". Better to compose than to decompose, but looking at just the one word out of context makes it look very out of place. Email is of course much harder to write than a wall post or a tweet, since you have to come up with To, Cc, Bcc, Subject and email text and since you can go well beyond 140 characters.