Threaded random writes are not any faster with Btrfs compression.
The PostMark test results for using Btrfs compression were not measurably faster than using Btrfs in its stock SSD mode without block compression.
Lastly, when measuring the time to unpack the Linux kernel source package, using Btrfs compression slowed down the process dramatically.
In a number of tests the disk performance was faster when enabling the Btrfs transparent zlib compression (such as with IOzone and Dbench) while with others (Compile Bench, Threaded I/O Tester, and Unpack Linux) the performance actually dropped and in the remainder of the tests there was no statistical change in one direction or the other. Once the Linux 2.6.36 kernel is nearing its release, we will be back with many more Btrfs benchmarks especially if the current Btrfs regressions that degrade its performance against the EXT4 file-system are hopefully addressed.