In my previous post (Installing a developer “Suite”), I talk about the flexibility of svn. As I anticipated, to achieve the integration of  tested and "validated" request, the way to use svn is to use the feature branching pattern. You can read more about it in the book “Version Control with Subversion” (see chapter 4 - page 137).

So to achieve this pattern, the has to follow the process, with the cost overhead. I think the distibuted model of mercurial as a smaller overhead in managing feature changes. This process is much simplier with a SCM that implements the process : developers summit their changes attached to a change request, all in the same trunk. Before a release the SCM manager just pick the validated chage requests. In such SCM, branchs are used to maintain releases, not the features.