I’m afraid I don’t have any great expertise to offer in the realm of Ukranian politics, so I’ve not really had anything to say about the ongoing crisis there. That said, I tend to agree with Dan Drezner that the internal dynamics of Ukranian politics suggest that the opposition candidate, Viktor Yushchenko, is unlikely to succeed in his effort to get the (apparently fraudulent) poll results overturned.
I do note, however, that the world press seems to be taking concerns about this election much more seriously than concerns about the Hugo Chávez recall referendum—where similarly large gaps between exit poll results and the actual tallies appeared. I also regret that the combination of occasionally-incompetent election officials, opaque electronic voting equipment, and conspiracy-mongering by people who should know better have coincided to leave the U.S. in a weaker position to contest suspect elections elsewhere in the world.