It works, but 24' later[1] I'm still confused :-(

I don't have strong feelings about either toolkit, but the switch (as opposed to both being available and equal) doesn't make sense to me. Apparently (11:48 onwards) the main driver for this seems to be cross-platform compatibility in general, and with SymbianOS in particular. That's a bit... naive to say the least. Portability is a lot more than skin deep, and there vast differences between the two OSs in basic things like file and network I/O, process control and signalling etc[2]. Even more significantly, the middle layer (d-bus, bluez, telepathy, gstreamer and so on on the Maemo side) is completely different. I'm sorry, but "recompiling and it more or less works" (17:26) just isn't going to happen for anything more complex than "Hello, world".

On the other hand GTK+ is reasonably cross-platform and there's even a port to Symbian OS underway. Glib has already been ported by Nokia too. Dropping GTK+, Hildon, all existing official apps[3] etc for "cross-platform compatibility" sounds like something that could only be imposed on the Maemo team from above by someone who has no real understanding of the technologies and issues involved[4].

Anyway, since it's fait accompli now, one question that becomes particularly important for prospective developers is: will Maemo 5 devices run Harmattan?

[1] Whatever happened to text btw, you'd think news as big as this would rate an announcement on maemo.org at least
[2] P.I.P.S. is incredibly buggy and if anyone considers it for production use they're in for some very interesting times.
[3] I don't envy Andre the reaction to the inevitable "WONTFIX for Harmattan"[5] storm
[4] But it does finally explain the castration of input methods :-(
[5] Not to mention the also inevitable regressions and new bugs introduced by rewriting everything for no good reason.