I've been using JMeter 2.2 for recording and running a couple of load tests on our new server. Now a lot of people are suggesting that Swing is ready for the desktop, at least for Linux. Well, my experience with JMeter on OS X is far from stellar:
- copy/paste/etc are not compatible with OS X defaults, but use the *shudder* Windows bindings
- there is no undo
- I can't get the data copy/pasted into other applications (textmate)
- you never know if jmeter has saved any test script, there is no feedback, and I've lost a couple of hours worth of proxied test script generation
- it is a true memory hog
As far as I can see, JMeter is a showcase of everything people expect from a Java desktop application. There is a whole world open for new and better open source projects to build a decent load testing application.