What wittelantaarnpaal said is correct. The ice wine itself is like Port Wine, it will not age after bottling. So the taste will not change much as time goes by. However, ice wine company usually will not use a very high quality cock and it can easily dry up if you don't lay it down flat when storing.
I opened an ice wine last year (March 2006) , which I bought from Niagara Falls in 2003, the vintage is also 2001. Even though I laid it flat and keep it inside my temperature controlled cellar, unfortunately the cock still got dried up. Lucky that the wax seal helped keep the oxygen out and prevented it from oxidation. The taste was still okay, just the color got turned a little bit gold, instead of pale yellow, and the cock got damaged, so I had to use a filter to decant it.
Wine is made for drinking, not for storage/display....enjoy it whenever you have a chance.
圖片參考:
http://hk.yimg.com/i/icon/16/1.gif
Happy drinking!