If you've been holding out on upgrading to the new Twitter interface, you no longer have any choice in the matter. The classic Twitter interface has been officially replaced by what the service calls New Twitter.

If you're on Twitter, you have likely started getting email notifications whenever a user replies to one of your tweets or mentions your username. Twitter previously only sent email alerts when a user received direct messages or gained a new follower. The move is a clear attempt to make the service more user-friendly for casual users. Many replies have gone unnoticed simply because users don't know to log in to check for them.

As you're surely aware, there's been a lot of hype surrounding the microblogging site Twitter lately, but what might be its coolest feature is being largely overlooked by the media: its ability to tell you what people all over the world are saying right this second. Never before has it been so easy to gain real-time insight into what people are saying about anything from products, businesses, current events and life in general.