Air Theme
So, since Air is coming along nicely (thanks Nuno), it was the time to make the files Lancelot needs for it. Although there are a few things yet to do, I’m quite satisfied with it. I’m even using Air as my Plasma theme now.
Scroll-bars
The second thing that all theme makers that support Lancelot should know, is that Lancelot now uses Plasma’s scroll-bars. So, you don’t need to make files for scroll-bars anymore.
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Keyboard support
Lancelot in KDE 4.2 introduced keyboard support. Now it is taken even further - now you can do /anything/ in L by using only the keyboard. The section and system buttons now can be accessed through standard accelerators (Alt + the underlined letter). For opening the context menu for an item in the menu, select it and press Alt+Enter.
KRunner actions
As you should already know, runners can now support various actions for results. You can access them in Lancelot via a context menu. Well, that was the good news, the bad is that I know not of any runner that provides any special actions. :(
Other things
There is now a logging system that remembers applications you launch, what you search for etc. Some new configuration options are also present, and the parts applet works better. There are probably other changes, but I can not remember them at the moment. :)
So, cheerio!