Twitter has made a small but significant change to the way you reply to people on the service, making this feature available straight from their profile page.
It's always been a bit strange that you couldn't interact with someone when you visit their profile, but Twitter haven't actually made a song and a dance about adding it – there's been not official statement as of yet on the new feature.
The feature means you can speak to someone that you don't follow in public, but you still can't direct message them unless they follow you back.
The @reply change is one of a number of minor tweaks to the site. Earlier this week an image uploader button was introduced.
With Facebook and Google+ integrating many Twitter-like features into their services by the day, it's likely that we will see this slow but steady evolution of Twitter continue.