Horizontal drinking is a skill I haven't developed . . . yet.
I have to say I am very impressed with the 2003. A little light in the mouth but with great flavor. I've read pineapple and vanilla on the front with spice on the end and agree. I will be buying more of it.
ramblinman and richnimrod - another interpretation of horizontal tasting is tasting multiple expressions from the same distillery to showcase cask management - this is especially true in the Scotch Whisky world - Glenmorangie being a readily available example with their Original, Quinta Ruban, Nectar D'or, Lasanta, etc. The obvious Bourbon example is Four Roses and tasting across their different mashbill and yeast combinations.
I think as yet horizontal tasting of whiskies has not been strictly defined. To borrow from wine terms, a horizontal tasting occurs when vintage is the common factor, compared from different producers. To give an example from that definition, then we would do a horizontal tasting of wheated bourbons from 99 from different distilleries. Now I know that you run a tasting company, and hence probably use the term horizontal tasting more than I, but I would term the Glenmorangie tasting you referred to above as a Glenmorangie tasting, or a distillery tasting or flight, but not a horizontal tasting. In fact, I prefer richnimrod's definition. I think of it as a wine term that doesn't really apply as much to whiskey. We like our own terms (Robert Parker is most everyone's bitch around these parts). Other whiskey people define it as: Horizontal - whiskeys of the same age or type from different distilleries. A google search of horizontal whiskey tasting places your site as the 5th result and the 4 results that come before define horizontal whiskey tasting differently from you and are all pretty much in agreement with each other. Just my 2 cents.
Wryguy - good points to keep in mind. There are so many ways to look at it - I usually make sure to itemize what's being tasted. And you are right that wine terms create confusion because concepts don't exactly translate - for example a 12 year whisky may have older spirit in it, unless it is a single cask, so it can't really compare against another 12 year spirit in the same way wines of the vintage year can be compared. The short-hand really doesn't matter either way. At the end of the day, call it what you want, and just taste the whisky. I do know this though - if you taste too much whisky you'll definitely be horizontal eventually.