I recommend EntitySpaces over dOOdads actually, there's no comparison in functionality and for 149.00 you'll easily recoop the effort of the cost, 10 fold ...http://www.entityspaces.net
Always the salesman...
There are not a lot of differences between EasyObjects and dOOdads because EO was born from dOOdads. There are a few syntactical differences, but the feature list is basically the same, because it was designed this way.
The main reason to use EasyObjects over dOOdads is if you have already made the decision to use the Enterprise Library. dOOdads does not support this.
Also, if you are restricted from using stored procedures, EO can perform all operations using dynamic SQL. dOOdads, I believe, only supports this for certain platforms that lack stored procedure support, such as MySQL 4.x.