Sun's decision to dump 1,300 people was expected.
Less expected was where they came from.
Included are people who worked on OpenJDK, desktop Java, the Java 2 Standard Edition (JavaSE) interface, and OpenSolaris.
The key question for open source is where these people will go. It's tough to find a job anywhere right now but there are many important Java-based projects, like JBOSS and Spring Framework, that are doing well in the market.
In the end this may be an opportunity for Java projects outside Sun to get themselves some good committers and more control over Java's direction.
Thus what sounds like a loss for open source could well turn out to be a win, making Java even more open and giving its governance more of the look-and-feel of Eclipse.
Regardless, it's still important to note that none of these people are isolated from the code base just because they have lost a paycheck.
For technology in general that's the biggest difference between this announcement and, say, Microsoft's brain dump.