You should be able to crossgrade your platform to Mac + upgrade at the same time for your Cubase.
Sequencers are a funny thing. Personal preferences are more subjective than keyboards! I really love Logic and cannot imagine switching over to any other even though my Logic for PC is no longer supported and is stuck at version 5.5.
But if I were to ever switch to Mac, I'll get Logic without even blinking my eye. And I will wait for the update to support intel based Macs. It's worth the wait. The plug-ins that comes with Logic itself is worth purchasing it. If you have lots of outboard gears (modules etc) that needs lots of midi control, Logic Environment pallete lets you connect them beautifully by connecting virtual cables. Great for complex midi that uses lots of tracks (and I use at least 30 midi tracks most of the time).
Again, this is a very biased opinion, although I did use Cakewalk Pro once upon a time. However, you may want to stick to Cubase since you are probably very used to it by now.