The primary focus of release 4.5 of Qt has been to improve performance. Qy says that 'significant performance enhancements were made to the graphics system, data handling, and the web engine. These improvements result in an appreciable performance increase in Qt-based applications'. 4.6 has also been ported to Apple's Cocoa framework providing full support for Apple computers. The release also improves integration with the WebKit web rendering engine allowing Qt application to seamlessly blend web and native content into a single user experience.
According to Qt, Qt Creator 'has been designed to deliver two key benefits: it provides the first IDE designed specifically for cross-platform development; and it enables developers that are new to the Qt framework to get up and running more quickly'. It currently only supports the desktop platforms, but embedded platform, including Symbian / S60, will be added in the next few months.
Qt for S60 is currently available as a technology preview, with the full release, based on Qt 4.5, due out this summer. While the release of Qt for S60 is significant in itself, the full benefits will only be felt if Qt continues its healthy development as a cross platform environment in general. Release 4.5 reinforces Qt's position as the market leading cross platform development environment. The new licensing and support models should drive higher uptake and usage and Qt Creator should make the platform more accessible to first time users.
Qt is an extremely important part of Nokia's software platform strategy and 4.5 is a very important mile stone. While there is little current impact (especially for end users), it lays important foundations for the future.
From the press release:
"Qt 4.5 is setting the benchmark for application development," said Benoit Schillings, Chief Technologist, Qt Software, Nokia. "With the performance improvements in Qt, the introduction of Qt Creator, and the release of the Qt SDK, developers looking for a native or a hybrid native/web application framework now have the power and flexibility they need."
Here's a brief video giving an over view of Qt 4.5. Further videos are available in Qt's dedicated YouTube channel.
Further information is available on the Qt website.