I've been waiting to upgrade since July (for the Bionic originally, but passed on that as it was a bit of a let down in the end and the Nexus had come along) so I can wait a little longer.
Unfortunately, I'm not sure my BB Storm 2 is going to hold out much longer. Its now steadfastly refusing to receive phone calls and will only call out about half the time. Skype has long since stopped working on it, though thankfully texts and emails still seem to be working. I'm using my wife's old BB Torch battery as mine died, but even that is now starting to fail...
Thank goodness for my XOOM, though having to use it as a phone at times is very embarassing!
So, short answer, I hope to be able to wait, but I may be forced to make a change soon.
At this rate, by the time the Nexus appears it might have some real competition (other high end phones designed for ICS) at least announced and maybe even with "firm" release dates. For now, I'm holding out, but the clock is ticking...