I have my favorites. The reason they are my favorites is because they share invaluable information freely. And not only are they engaging and interactive, they brighten my day.
They include:
I want to know who your favorite marketers are on Twitter. Who do you follow that helps you with your marketing? Do they share valuable advice, tips, news? Share their name, username and why you follow them. Please include their company name and marketing specialty, if applicable.
Who do you follow?
I would be negligent not to mention my own account: Laura Lake. You'll stay up-to-date on what's going on in the marketing world. All articles and posts get tweeted.

