pl/perl in postgresql 8.0 beta

I noticed the changelog for Postgresql mentions some interesting things 
in relation to pl/perl:

"New Perl Server-Side Language
A new version of the plperl server-side language now supports a
persistent shared storage area, triggers, returning records and
arrays of records, and SPI calls to access the database."

Does anyone have some working examples of pl/perl using these new 
capabilities? The documentation in the 8.0 beta for pl/perl has not been 
updated and I'm looking for this information.

Also, is it still possible to use untrusted pl/perl in 8.0, and if so, 
what are the steps for setting it up?

Thank you,
Brian