The JavaOne Store Metric
This is a picture of the JavaOne store on the last day:
(The green arrows point to empty shelves.) The store was still open... this isn't a shot of the employees packing up, but rather a shot of some guy hoping to find something to take home. And keep in mind that this guy probably already has at least five t-shirts he got for free this week.
Yes, I think this is all the evidence we need of Java's continued success. People were snapping up any Java or Duke-branded thing they could find, from mugs to shirts to pens to really expensive things like the leather Java jacket.
I'm making light of this -- after all, they're just t-shirts. But take a moment to think about why attendees -- Java developers, mostly -- couldn't spend money fast enough on Java-branded items. What does that say? And you might think you're immune... that people buying this stuff are idiots. That you wouldn't have spent good money for stupid shirts and mugs. But lots of us did. The only reason I didn't spend more myself is that they ran out of the really cool "thrasher Duke" shirts that featured Duke skateboading down Lombard.
If buying logo items is any indication of how developers feel about Java, and I think it is, Duke has a very healthy future ahead of him, and we can rest assured that the Java community is still vibrant and active and most importantly, can still afford t-shirts.