Well, well, I didn't think that it would happen, but I will be working this summer on integrating Plasma into Kontact's Summary Page thanks to Google Summer of Code. It shall be an awesome summer full of Win at this point, I'm getting really excited about how things are shaping up now.
Basically the idea is to start with the creation of a Dashboard that any KDE application can load in their application as a KPart and make it really easy for them to do that. An application writer doesn't have to know or care about Coronas or Views or any of that, it's as simple as loading the kpart and writing the plasma applets which can be done in pretty much any language imaginable these days, and tools such as Plasmate make it even easier.
This KPart will be done in cooperation with Siddharth Sharma, whose proposal to integrate a similar dashboard into the Skrooge finance application was also accepted into Summer of Code. By pooling our efforts in this area, we can make it extremely simple to bring Plasma to any application in KDE.
The biggest problem that we are having with our work right now, which will be solved soon, is pulling ourselves away from depending on kdebase-workspace, mostly for the Widget Browser. I will be looking at reimplementing that code over the next few weeks before GSoC "officially" starts. I'm thinking something subclassed on KMenu, that way it can be added as an action pretty much anywhere, and be reusable by other applications. The Widget Browser has some fairly complex code though :)
After our KPart is all said and done, we'll be branching into the development of our separate applications' applets. Hopefully through the writing of these applets I will finally be able to wrap my head around Entity Tree Models, and be able to contribute something really awesome to the KDEPIM team.
I don't have any mockups of the finished product yet, but you can see a few of the applets mocked up, and the rest of my GSoC proposal [here](http://rix.si/files/soc-2010.txt). I blog quite a bit, and am on [identi.ca](http://identi.ca/rrix), for those interested in following this development, or you can listen to me rant about ETMs in #plasma on irc.freenode.net ;)
See you soon!