A while ago i posted a topic about the change of allowing = NULL (technically illegal) in 7.2 Postgres.

Well now i've just noticed another one, and people wanted to know if i found anything else.

The previous syntax for date and time conventions suggested that:
select date('now') + interval('2 day 14 hours 12 minutes');
should always work.
I've now discovered that interval('') creates a syntax error.
The new syntax is interval '';
so the above example would be:
select date('now') + interval '2 days 14 hours 12 minutes';

Hope this is helpful (and .. obviously... that i'm not wrong )