What can we expect from the Solar Flare X2?

A good aurora at very high and low latitudes in a few days. Other than that, not much. This happens a lot, actually, just not in the last few years. These kinds of flares are common during high periods of solar activity, which peak every 11 years.

Geomagnetic storms are disturbances in the earth's magnetic field due to incoming streams of charged particles. They can be severe enough to disrupt power, as happened in Canada in 1989, but that was only for a few hours and that's extremely rare. The only other notable event I know of on that scale was 140 years earlier, when the telegraph system was disrupted for a period of a few hours in 1859.

The main thing we expect to see from these events are spectacular aurora displays. And indeed, on the Space Weather site right now, just below the article about the CME that you apparently quoted without attribution, is a photograph of the first such auroras.

http://www.spaceweather.com/

According to the article, here's what to expect: "Indeed, a series of CMEs en route to Earth from exploding sunspot 1158 are expected to arrive on Feb. 15th-17th, prompting bright displays at even lower latitudes."

the Northern Lights should be spectacular for a few days, and you might see some power overloads and blackouts here & there on the electrical grid, but aside from that... not much.

Geomagnetic storms are really just ions and particles that are blown out from the sun. They may miss Earth altogether, but if they hit, they can alter the structure of Earth's magnetic field for awhile, and cause some very cool auroral displays. They can also knock out or otherwise affect orbiting satellites.

Solar Power Design Manual : http://solar.eudko.com/?coN