In one respect, this might be really useful, especially to new users. I know many people that cannot see any use for twitter whatsoever. Clearly, i'm not explaining it correctly. ;) Instant timeline might help solve some of that newbie disinterest.
Twitter analyzes your contacts and uses information like who they are and who they follow on Twitter to guess which accounts and topics might interest you. It then shows you those tweets in your feed. So if your friends are foodies, you will see items about recipes and food trends. If they are football lovers or fans of Ellen DeGeneres, you will see National Football League video highlights and tweets from comic actors.
The result is a timeline of (hopefully) compelling tweets without your needing to follow a single account.Twitter Tests Instant Timeline [bits.blogs.nytimes.com]