Just to provide a data point: I started having problems getting to wordpress.com today as well.
After a few failures (in Chrome, IE, Firefox), I decided to check it out via dev tools (in Chrome)... recording the Network and Timeline.
Eventually wordpress.com came up.
From the Network tab it seems there is one request that was holding it all up:
http://s0.wp.com/_static/ took 2.3 minutes to show up.
The full request includes more, of course:
The rest seemed to be delivered just fine (in ms, rather than minutes)
I'm connecting via cable (Cox Cable) from North-Central Florida (USA).
I tried various browsers, with the same results. Most commonly Chrome 21.x
UA string matching that: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/21.0.1180.83 Safari/537.1
I did not try to clear cache, or disable all plugins, sorry - but now that it all got delivered, even incognito mode seems to work without the huge hickup...