I’d like to start with a few words on the differences between 3.0 and previous versions.
You can think of v3.0 as a brand new product as we started from zero. I will point some of the reasons for this decision. As you know, requirements for web sites have changed quite a bit in the last few years and they will continue to changing. That’s why we need to offer more extensible and more scalable architecture. The changes we had to make ware so vast that we decided to start from the very beginning and with all the experience we gathered to move on the next level.
Even though the backend schemas are completely different and the data access is relying on very different technologies, it is fairly easy and straightforward to translate data from old versions, maybe with some missing parts of course.
The real problem lays in the layouts of the old pages. In the previous versions we used the RadDesigner to store and generate HTML output.
The RadDesigner generates deeply nested tables which lead to several problems:
1. It is difficult, sometimes even impossible to create WAI compliant sites.
2. It is difficult and tricky to achieve certain layouts.
3. The layout can’t be controlled through CSS.
4. Worse performance on the client side (particularly with IE6)
These are some of the reasons why we decided to drop out RadDesigner and leave the layout creation outside Sitefinity’s GUI. Instead, we will provide a rich set of predefined master page templates and CSSes that can be easily modified to suit your needs.
So the big question is how do we translate nested cells into content placeholders and make the page look the same? My guess is we'll need some sort of artificial intelligence here. I’m kidding but I really doubt we can be 100% accurate in all cases and such converter will require quite an effort.
My suggestion is, if you really need to start developing now, start with the beta version. We will try to make upgrades as seamless as possible. In fact, we already have some clients developing real-life sites with the beta version.
All the best,