Lots of people who are not at all fans of Trump, but who are experts in the field, have said this is bogus fearmongering. Go read erratasec, or look at what Glenn Greenwald is saying.
When you can only find credulous, partisan hacks like CNN, Huffington Post, Washington Post, etc. pushing this narrative, it's time to wake up and realize that you're being lied to. The evidence is terrible and the excuses are worse. We're supposed to believe that we're being taken over by Russia, but they're never going to give us any evidence because it might compromise a source or method? If that were actually true, what then would be the point of *having* these intelligence departments in the first place?
The real problem is that they've given us the "evidence" they have, complete with ridiculous rumors from hoax documents, and it stinks. They try to talk up their MI6 source, but never mention that nobody could find any worthwhile corroborating evidence for the entire memo after spending months trying. All they've found is proof that the memo has people in completely the wrong countries, meaning their "raw intelligence" is a load of crap.
Worse, they're now talking up protests and the head of the National Guard in DC refused to stay on, he's quitting during the Inauguration and all the Democrats are planning to avoid the area. They're busing in lots of protesters, too. I wouldn't go within a thousand miles of there if I could help it.
Expect shenanigans. The loonies are high strung enough that someone is almost guaranteed to do something stupid. Trump isn't as stupid as he's assumed to be, though. He kept on his private security for a reason. If you're stupid enough to take part in the shenanigans, you'll get exactly what you deserve.