We need to distinguish between sea ice (a ~1m thick layer of frozen seawater), and land ice (up to 3000m thick layer of compacted snow). Sea ice is quick to respond to climate change (because it's so thin), and has a large seasonal component to its extent. Land ice is much slower to respond, and harder to replace once it's gone.

Antarctic sea ice extent has been increasing, largely because of a change in wind patterns. Winds blow ice away from the coast, leading to more open water, which leads to more sea ice formation. Even though Antarctica is getting warmer, it's still much too cold to melt sea ice in most places, so climate warming isn't having a huge direct effect on sea ice.

However, the land ice in the Antarctic is almost certainly decreasing (exact measurements are quite hard), and the trend is definitely towards more ice loss. Ice shelves, although floating, are the outer extremes of this land ice.

This is a good review paper on the subject of the mass balance of land ice: http://www.vliz.be/imisdocs/publications/248038.pdf