Adaptive optics works great at infrared wavelengths. It does not (yet) do well at visible wavelengths. Even the 2.5 meter mirror of Hubble has better resolution at visible wavelengths than the 10 meter Keck mirror due to atmospheric blurring. Further, adaptive optics is only effective over small fields of view (such as a single star and planet). One can not take a wide field view of a nebula or a galaxy and get a high resolution adaptive optics view over the whole field.

Yes, the text is wrong. There are several methods for detecting the presence of an exoplanet, though the "wobble" (aka radial velocity) method has so far been the dominant one. One can also other methods like transits (like Kepler), astrometry, gravitational lensing, and pulsar timing. After Kepler has completed its mission, there will likely be more planets detected by transits than by any other method.

That depends on what you mean by "a really decent" image. We can see surface features on Pluto, albeit still a very fuzzy view. These exoplanets are unresolved - we can see they are there, but we can see absolutely no details. Further, recognize that a Jupiter-size planet is over 100,000 km in diameter, while the largest Kuiper Belt objects (KBOs, which includes Pluto) are at best 3,000 km. Surface area goes as the square of the diameter, so you can see that the amount of light reflected will be vastly larger for a giant planet than for even the biggest KBOs. Plus KBOs tend to be rather dark and reflect little of the light that hits them (low albedo). BUT, this will change in 2015 when New Horizons gets to the Pluto/Charon system and shows the details.

There are several direct images of exoplanets available. Hubble took one of a planet around Fomalhaut, which was announced the same day that Keck announced three planets around HR 8799 (Nov 13, 2008). The next week, ESO announced a possible planet around Beta Pictoris, which has recently been confirmed. What these folks at Gemini are saying is that they announced a possible direct image earlier in 2008, which they have now confirmed, so theirs was really the first. It is a game of "who got the first direct image of a planet around another star?". It doesn't really matter, but it is very cool that we can now directly see not only the 8 planets in our solar system, but also at least 6 more in other solar systems. At some pivotal point in the near future we will have more pictures of planets outside our solar system than within it!