The above link leads to following articles:

This image shows temperature trends for the icy continent from 1982 to 2004. Red indicates areas where temperatures generally increased during that period, and blue shows where temperatures predominantly decreased..
Although Antarctica warmed around the perimeter from 1982 to 2004, where huge icebergs calved and some ice shelves disintegrated, it cooled closer to the pole.

Why is Antarctica getting colder in the middle when it’s warming up around the edge? One possible explanation is that the warmer temperatures in the surrounding ocean have produced more precipitation in the continent’s interior, and this increased snowfall has cooled the high-altitude region around the pole. Another possible explanation involves ozone. Ozone in the Earth’s stratosphere absorbs ultraviolet radiation, and absorbing this energy warms the stratosphere. Loss of UV-absorbing ozone may have cooled the stratosphere and strengthened the polar vortex, a pattern of spinning winds around the South Pole. The vortex acts like an atmospheric barrier, preventing warmer, coastal air from moving in to the continent’s interior. A stronger polar vortex might explain the cooling trend in the interior of Antarctica.

http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=1...

In Sciencedaily Jan 22nd, /2008

The first evidence of a volcanic eruption from beneath Antarctica's most rapidly changing ice sheet has been reported. The volcano on the West Antarctic Ice Sheet erupted 2000 years ago (325BC) and remains active.
Co-author Professor David Vaughan (BAS) says,"This eruption occurred close to Pine Island Glacier on the West Antarctic Ice Sheet. The flow of this glacier towards the coast has speeded up in recent decades and it may be possible that heat from the volcano has caused some of that acceleration. However, it cannot explain the more widespread thinning of West Antarctic glaciers that together are contributing nearly 0.2mm per year to sea-level rise. This wider change most probably has its origin in warming ocean waters."

http://www.sciencedaily.com/releases/2008/01/080120160720.htm

Then, on March 4th 2008

"Could Volcanic Activity In West Antarctic Rift Destabilize Ice Sheet? The West Antarctic rift is a region of volcanic activity and crustal stretching that is roughly the size of the western United States (from Salt Lake City to the Pacific Ocean).
It is interesting nevertheless, because volcanic eruptions beneath the ice could destabilize the ice sheet, leading to as much as 25 feet of sea-level rise. How likely is it that this could happen is a question scientists have debated for over a decade. LeMasurier addresses the question by comparing the West Antarctic rift with similar areas of crustal stretching elsewhere in the world.

The comparison shows that volcanic activity in rifts is most common where the land is a mile or more above sea level, and rising, which can readily be seen in Antarctica along the Transantarctic Mountains, and in the Pacific coast mountains of Marie Byrd Land. The large sub-sea-level interior of the rift does not, therefore, seem to be a likely place for present-day volcanic activity.

This is good news, because the sub-sea-level base of the West Antarctic ice sheet is already especially vulnerable to warming of the atmosphere and surrounding seas. However, this study also shows that the land in West Antarctica has been rising beneath the ice sheet in some areas and subsiding beneath it in others, over roughly the past 25 million years."

http://www.sciencedaily.com/releases/2008/02/080229183818.htm

Hansen said he will soon publish a paper on Antarctica

Furthermore that image is old(1982-2004 trend), the new one is available here(1981-2007 trend):
http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=1...

Just three more years changed drammatically temperature trends inside antarctica due to strong short term fluctuations.
That's why antarctica trend are so uncertain.
Anyway there's no doubt antarctica peninsula warmed at a fast rate during last 50 years and ice shelves respond to long term temperature variations, it's not sea ice.