I think this is a good change. Bravo!
It will be hard not to refer to "Singinst" anymore as it did trip off the tougne, but I guess "The Singularity Institute for or against Artificial Intelligence, depending on which seems like a better idea at the time" was never really on the cards.
We could call it the Machriarchy.
(MACHine intelligence ReaseARCH Institute, and just stick in the 'I')
http://singularity.org/blog/2013/01/30/we-are-now-the-machine-intelligence-research-institute-miri/
As Risto Saarelma pointed out on IRC, "Volcano Lair Doom Institute" would have been cooler, but this is pretty good too. As the word "Singularity" has pretty much lost its meaning, it's better to have a name that doesn't give a new person all kinds of weird initial associations as their first impression. And "Machine Intelligence Research Institute" is appropriately descriptive while still being general enough.