(provoked by: IBM's item on EA and SOA)My summary of the lessons
1. SOA addresses only a subset of EA domains (i.e. services) and can leverage other EA domains (e.g. information architecture, system management, operational architectures, rules/decisions architectures, function/process architectures, control architectures etc.).
2. SOA governance should leverage EA governance. The service model(s) should be developed and maintained by the SOA experts just as other aspects of an EA should be developed and maintained by their experts e.g. data/information, architecture, rules/decisionms, process arch, systems etc. The Services model(s) should be referenced from the EA and architecture review boards should consider services governance.
3. Ideally the funding models for services (and common infrastructures, and functions) should be based on an enterprise level not a project level.
4. SOA infrastructure is an enterprise asset (just like any other infrastructures e.g. information/data, rules/decisions etc.) and should be managed as part of the enterprise system management and comply with enterprise policies e.g. security.
(see also: SOA's need to be underpinned by better management)