I have experience in using Umbraco.
The release of Orchard worths taking a look at it. I'd like to compare both products. I read "Creating a custom field type" (http://www.orchardproject.net/docs/Creating-a-custom-field-type.ashx).
I must admit I was stuned: so much code needed to add a couple of fields? A CMS is supposed to make things simple.
Orchard is still very young. Do you plan to improve the user experience when creating custom fields? I mean a way to create then with the help of the UI.
Please don't see any offense.