Did someone test it before releasing.
I am under the impression no one tested this.
Yes, I tested it on Wednesday night. I immediately found a graphics problem, running on a Samsung NC10 Netbook (32-bit). Whenever there is a new lubuntu iso made available for testing, I always test it out. I reported the problem to this (and other) mailing lists. I even have a list of checks I perform on new isos.
On Thursday, I performed more tests, with a view to helping anyone trying to fix the problem. At the end I took some rather blurry photos of the graphics problem and emailed them to the lubuntu-devel mailing list.