No really, he said it. He would've been on the short list of people I assume would never say it. But there it is.
Here's the thing; I think that this is a lot like Gartner's IDS declaration (which he cites). IDS went through some product positioning changes (IPS, UTM, DLP, etc.) but the core idea and technology is still there, and guess what? The original IDS use case is still viable. Sure the attacks have changed, but having a sniffer that can search for known-bad and known-strange traffic on the wire is very, very useful.
So I assume that we are in the midst of a product positioning shift around SIM. Raffy's point that SIM schema are IP-centric and rules are based around correlating firewall and IDS events is true. But most of the vendors have already acknowledged this and are developing content to focus on other log sources. Either way, the use case is here to stay - the ability to search and correlate log events is highly useful, and will continue to be. You may call it "SIEM" or "IT Search" or "log management," but it's the same core concept, repurposed to address the constantly changing security environment.
One final note for vendors from the SecOps trenches: I am not open to a replace/resell on the basis that SIM is old and whatever-you-call-it-now is new and better. My SIM, like my IDS, contains custom content that our team has developed to keep on top of changing threats, including application attacks. SIM, like IDS, succeeds when you put talented security professionals in front of it and let them tune it and manage it like a tool. But it will fail miserably if you are hands-off with it.