I've been saving this bottle for a couple years to see what a little age would do for a nice local riesling. In short, not much. This wine is gorgeous and will last a lot longer and maybe even improve.
The 2005 Holleran Riesling Chehalem Mountain Vineyard is light gold in color with a pretty peach, pineapple and diesel aroma. There's great freshness here even after a few years in the bottle. The flavors are penetrating and precise, with minerally acid and terrific cut to the pineapple and diesel flavors. The long finish even has bits of raspberry, something classic to great Mosel riesling. It's still on the simple side, but so full of character. Age should soften it a bit and add earthy complexity to the whole package.
How long will that take? I'd guess another five to ten years, and it will probably last a lot longer than that. Having had Oregon riesling back to the '70s, I suppose it should be no surprise. Excellent wine.