An old friend of mine started talking about Guerilla SOA a few years back and got into some interesting debates around it. Ignoring the fact that some of G-SOA is flack about the need (or not) for vendor specific SOIs (always a good thing to push if you're working for a consultancy firm), one of the important aspects that I take from this is the incremental approach to SOA. Whatever you call it, the concept of taking things one step at a time when you approach SOA rather than trying to do a big bang approach is fairly obvious and intuitive. We're used to working in that way for many different things: you don't have to know all of Java in order to write HelloWorld; you don't have to understand how your car engine works in order to drive it etc. etc.
This incremental approach to SOA is something we've been pushing since the very early days of JBossESB and it's embodied in the latest release of our SOA Platform. The feedback we've been getting is overwhelmingly positive, so we've also been doing this within Overlord. I'm not sure if we'll call this Guerilla Governance (G-Governance?) but the principles are the same: start small and build up as you gain experience and as your needs evolve. A flexible SOA Governance infrastructure should adapt to you while at the same time encouraging good governance practices so that you can adapt to it. This is why we've started with things like DNA/Guvnor and Process Governance, as they satisfy well defined needs on an independent basis but also within the whole Overlord infrastructure as and when we get there. SAMM is a little more invasive as far as governance is concerned, as is the forthcoming work on Policy Enforcement Points and SLAs. But more on them in the future.
So if you're looking to deploy your favourite SOI and are concerned about governance, don't think you necessarily have to buy in a complete solution immediately. (I'm not even sure there is such a thing as a complete solution!) Look for something that can grow with you and even better, something that you can influence with your own policies and approaches to governance.
And if you're using JBossESB or our SOA Platform, take a look at the Process Governance work. As soon as you start to tie together more than a couple of services, something like this (helping you to write and enforce provable correct choreographies between arbitrary services and across arbitrary complexities) is essential.