Just logged on a I was like WTF! On first impressions it seems alright actually and definitely runs faster and smoother. Like any website changes they always cause an uproar and it'll certainly take some getting used to.
Personally I'll give a try for a couple of days no doubt revert back to the full site, just like I do with every other website I use. I'm just not a massive fan of mobile formatted sites in general.
Good to see the forum isn't getting left behind in development though.
