Process Substitution backgrounds the command list?

[Bob Proulx]

I am confused by the order of operations of this following:

  $ { echo hello world | tee >(md5sum 1>&2) ;} ; echo goodbye
  hello world
  goodbye
  $ 6f5902ac237024bdd0c176cb93063dc4  -

Shouldn't bash wait for the subprocess finish before the next command
is invoked?  I did not expect the >(list) to continue to run in the
background after the entire pipeline returned.

Is there a way to explicitly wait for that process in order to
synchronize subsequent operations?

Thanks
Bob

P.S. I am using bash 3.1.17(1)-release from Debian stable Etch.