I like the idea of having a chromebook, but literally it doesn't do anything beneficial for me. Every HTML5 based service I've tried either has too many stability issues, or they're not very robust. There's a huge difference in using a web based application, vs a native. And honestly, I don't want to wait those extra few seconds just so the browser can render a gradient.
I've been using Photoshop since 1998/9, Dreamweaver for 10 years now, and I really don't want to give up these professional tools for something that is so lacking in so many ways. I'd rather be using the MacBook Pro with my full blown CS6. And the thing is, it's probably even lighter than that ThinkPad anyway, and I can do EVERYTHING on it.
I don't do many online things either, I don't even use Dropbox. I learnt earlier on that keeping 20GB worth of stuff uploaded somewhere is not worth it. I use Evernote, but I'd rather buy the book the notes came from, or even print something out (you can plant a new tree, and you can recycle and remake paper, it's OKAY people!). Most of my app usage is productivity stuff that is offline, other than updating it, and I prefer keeping my books and music offline too.
ThinkPads are nice, although I've had three with motherboard issues that caused them to lockup if you moved them around too much. I have a late 90's one that's perfectly still fine though.
I just think they're too clunky.