If you are active on Twitter then perhaps you have already seen some excellent lists of twitter hashtags for writers. (publishyourownebooks.com)
Other notes — our official twitter hashtag is #gfreerally — so go follow to see all the amazing recipes and updates of our ratio endeavors! (jenncuisine.com)
For hard evidence that ebooks are competing with print books for readers one need look no further than the experience of many American University Press Publishers and other academic publishers (cf many discussions that took place at the AAUP2010 annunal meeting (twitter hashtag #AAUP10). (blackplasticglasses.com)