Ok. Being borderline trollish here, but if I read this article, this means to me "yeah. we are using a technically inferior solution and thus risking data loss and increasing the workload on our developers because our HR department gets more resumes if we search for an in-house database specialist".
Postgres usually does its thing and does it well. You usually don't get weirdness that requires you to even hire a specialist. And if you do, the consultants around are great and actually understand the problem.
As other people here have said: If you find someone listing PostgreSQL experience on their resume, you know they have the experience. If you find somebody listing MySQL, you'd have to check whether they are just listing it because they have heard of it or whether they really understand the problem domain.
So. DB specialists are settled. What about developers? PostgreSQL and MySQL are close enough in what SQL constructs they support (no wonder - MySQL provides a subset of SQL anyways), so coming from MySQL to PostgreSQL usually is trivial and the few things that are unsupported unix_timestamp() for example, you can write wrappers for if you really need them.
Of course, developers will at first find it strange that they can't, for example insert a 200 characters string into a varchar(10) column, but even the most braindead developer sooner or later will understand that silently truncating data usually is a bad thing.
No. The arguments listed in that article are just fear of the unknown and total non-issues (in german, there's this saying: "Was der Bauer nicht kennt, das frisst er nicht" - ever so true).
I'm glad I can work with PostgreSQL day-in, day-out. I'm glad I migrated that huge application from MySQL to Postgres back in 2000. I'm glad I did not touch MySQL for serious stuff ever since then.
I understand if you need to use MySQL if you want to run some software that runs only on MySQL. But if you are writing your own application, there's just no reason not to got with the real RDBMS.
/rant.