CSLA.NET architecture

It depends on what you mean by enterprise level ... what is an application? Is the desktop application web based? Intermediate? Shared library?

The CSLA has good points and bad points. I asked a similar question . Look at this and this

My criticism is that it is very verbose and sometimes complex and that it encapsulates a data layer inside its classes, which means TDD is tough with it.

However, it was designed for business and gives you brilliant functionality right out of the tin. book is worth reading.