Caol Ila is quite interesting and definitely a favorite of mine. While it is an Islay malt, from which you would expect peatiness and power, it is quite a bit lighter than its Islay cousins Laphroaig and Lagavulin while still retaining the "island character."
Perhaps it is due to the location of the distillery, overlooking the strait between Islay and Jura (in fact, Caol Ila means "Sound [strait] of Islay" in Scottish Gaelic), which shields it from the Atlantic wind and surf and creates a lighter style.
I tried the 18 year old version several years ago before I began learning to taste single malt, and liked it quite a bit. So when I spotted the 12 year old the other day, I decided to give it a try, and very happy I did.
The nose is peaty but light, maybe a whiff of oiliness in the background, and it opens up well with or without water.
It is slightly sweet to taste, but light - definitely an "Islay starter-kit" without the over-strong peat character that devotees love but cause newcomers to Scotch to turn up their nose in disgust (personally, I come down squarely in the camp of the peat lovers these days, but I can easily remember the first single malt tasting in which I continually uttered the words "tastes like medicine - never again!").
Score: B+ (a great introduction to the Islay style, and a good but not excellent value at $55)