You may have noticed that twitter has made some changes today; Twitter's homepage has been redesigned into a more formal layout. The top tweets have been replaced with popular tweeters profile pictures which take you to their twitter page when you click. Maybe this was the reason for the downtime earlier. The background image is a map now, which fits with the slogan "instant updates from your friends, industry experts, favorite celebrites, and what's happening around the world." This comes just days after Twitter announced on their Twitter blog, that they have made it much easier to find and follower Twitter accounts based on your interests. See here Discover new accounts and search like a pro. I'm glad to say that the old twitter design is still there for tweeting.