What are the benefits of using ORM over XML Serialization/Deserialization?

Answer 1

First things first, unless you're willing to give up using stored procedures, NHibernate will not provide much benefit, and the Entity Framework will probably frustrate you.

In my opinion, it seems like you are trying to re-invent the wheel. By switching to use a commonly accepted ORM tool, you can be confident that your project will be sustainable in a high-traffic situation (you can use tools such as NH Prof or EF Prof to help out here). In addition, using an ORM will provide many more benefits along the way including increased maintainability and eventual productivity after a small ramp up period.