I'm still sat on the fence and so haven't bothered with the pre-order, yet. And the DSF strings carrot isn't up my street at all and I'm not that bothered about being able to download a day early either. So I'm just keeping my eye on things. Not because I think there'll be any problems with X2. I am quite confident that X2 will work straight out of the box with just a few minor patches required over the coming months.
As others have said here and elsewhere, X1 was the big change with the GUI and stuff, and X2, for me, looks much the same as X1, but with a load of extra goodies, the biggest and bestest for me being the development of take/automation lanes and getting rid of those pesky layers.
When I do get X2, and it will not be to long after the release, I will probably get rid of X1 and all the bits and pieces that came with it and do a complete fresh install. I know you can run versions side by side but I've only got a couple of small SSD's for my programs. And since getting X1 a few months ago I've hardly done anything with it other that get to grips with the new interface and experiment a bit with the new synths I recently purchased. So stripping everything back and starting afresh with X2 doesn't sound like too much of a big deal for me.
@ Norrie - Out of curiosity I followed the link to your website and had a look around. I hope you don't mind me saying but you don't half remind me of Neil Peart (you might of heard of him... plays drums for a band called Rush).