The Tech Report writes Google's Chrome browser may get support for Firefox-like extensions by late May:
However, blogger Nicholas Moline spotted something interesting in the program for the Google I/O developer conference. The page describes a session entitled, "Developing extensions for Google Chrome." Clicking on the session name reveals the following text:
Learn how Google Chrome makes it easy to write extensions using the web technologies you already know. This talk will cover the basics of the extension system (distribution/packaging, installation, updates), as well as the different APIs to enhance with the browser.
Since Google I/O is taking place on May 27-28, the message seems clear: Chrome will have some degree of third-party extension support by then.