Angela Colter outlines the case for, and methods of, content testing.

Luke Wroblewski talks through the changes in the Twitter sign-up process and how it improved their engagement measures.

From the site: Fluid builds user interfaces, designs commonly used interactions, teaches others how to build good user-centred designs, and works with other software projects to integrate our solutions into their applications. Fluid is a project of the Inclusive Design Research Centre, OCAD University, funded by a grant from The Andrew W. Mellon Foundation.

By Paras Chopra.

Nice design.

Roger Johansson has made a test page for new HTML5 input element types. Mobile Safari, Safari and Opera are already recognising some of these.

Jason Grigsby’s notes on targeting the screen orientation of an iPad via CSS.

Jacek Galanciak’s sort and filter animation plugin for jQuery.

Anders Toxboe provides a lot of links.

Jaan Orvet and Andreas Carlsson present a progressive approach to donation form UI design.

Kimberly Blessing’s approach to semantic progress labels on checkout pages.

Richard Rutter discusses PolyPage, a jQuery plugin for building context-dependent wireframes (e.g. logged in, not logged in) using cookies.

Mark Boulton and Leisa Reichelt on developing user categories for the Drupal 7 user interface redesign.

Brian Christiansen introduces a new podcast from UIE. The format is one question from a caller, and an answer from Jared Spool and Robert Hoekman, Jr., per episode.

Robert Nyman on Smush.it, an image optimization service.