2.0.5 had an off-by-one error in the ESI handling causing includes to fail a large part of the time. This has now been fixed.
Try harder to not confuse backends when sending them backend probes. We half-closed the connection, something some backends thought meant we had dropped the connection. Stop doing so, and add the capability for specifying the expected response code.
In 2.0.5, session lingering was turned on. This caused statistics to not be counted often enough in some cases. This has now been fixed.
Avoid triggering an assert if the other end closes the connection while we are lingering and waiting for another request from them.
When generating backtraces, prefer the built-in backtrace function if such exists. This fixes a problem compiling 2.0.5 on Solaris.
Make it possible to specify the per-thread stack size. This might be useful on 32 bit systems with their limited address space.
Document the -C option to varnishd.