What’s Coming in Internet Explorer 10

When Microsoft released Internet Explorer 9.0, we hoped it would mark the end of their traditional 2-year release schedule. Less than one month later, the company has announced their plans for IE10 and released a Platform Preview download.

Unlike previous chunky updates, IE 10 currently offers a few minor improvements over IE9 …

New CSS3 Properties

IE10 will support CSS3 gradients (W3C Draft Specification) and the following properties can be applied to element backgrounds:

-ms-linear-gradient
-ms-radial-gradient
-ms-repeating-linear-gradient
-ms-repeating-radial-gradient

Usefully, Microsoft has provided a CSS Gradient Background Maker on their Test Drive website.

If floated elements are causing you grief, IE10 will offer several alternative layouts methods:

CSS3 Flexible Box Module — or “Flexbox” (W3C Draft Specification)
CSS3 Multi-column layouts (W3C Draft Specification)
CSS3 Grid Alignment (W3C Draft Specification)

Flexbox and multi-column layouts are supported in other browsers (with vendor prefixes), so the technologies should become feasible if you’re happy to accept a downgraded appearance in IE9 and below. Assuming no other vendors beat Microsoft, IE10 will be the first browser to support Grid Alignment.

JavaScript (ECMAScript 5) Strict Mode

A new use strict; command puts your code into strict mode. This offers more robust parsing, improved error checking, and will highlight potential compatibility issues with future editions of the language.
New User Agent

IE10′s new user agent string is:
Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.1; Trident/6.0)

It will be interesting to see if IE befalls the same issue Opera encountered when moving to version 10. They discovered many sites using flawed browser sniffing techniques which only parsed the first digit, assumed the browser was Opera 1, and degraded or blocked the site. To counteract the problem, Opera uses the version 9.80 in its User Agent string.

While browser sniffing stinks, it’s enjoyed a recent resurgence in popularity as developers start supporting mobile devices. Perhaps it’s time to double-check your code?
When Will IE10 be Released?

Microsoft has not committed to a date. There are rumors that beta 1 will appear during September 2011 with the final edition appearing in March 2012 — 12 months after IE9′s launch. That seems a little sedate given the small number of improvements. Perhaps Microsoft will surprise us with an earlier release or additional features? (HTML5 forms please!)

Whatever happens, Microsoft seems likely to break their 2-year release routine.