I think there's a prevailing theme there. It seems that back in the day most compass manufacturers took quality control more seriously. Their products cost more relatively speaking but were made to higher standards.

To second Ken's experience, I have had my eye on a pretty old Silva, possibly from the late 70's, in near perfect condition (apart from the cosmetic nicks and scratches). Understandably enough, its owner would not part with it under any circumstances. Also, I have an Eastern European military issue liquid-filled compass in my collection, made ca. 1980 and with a lot of mileage. The capsule is still perfectly free of bubbles or defects.

Compare that to the current market offerings. Despite its excellent design, my ca. 2006 vintage MC-2G Suunto had some flaws even before the fatal capsule leak. The bezel developed slight play from use, nothing catastrophic but enough to affect the accuracy of readings up to maybe one degree. Not nice, or at least not what one would expect from a top-of-the line model made by a leading brand. I can attest from personal observation that the currently produced MC-2G is made to even lower standards.

I don't know, maybe I'm a little harsh on Suunto but I'm not the only person who's had serious issues with their products. A little while ago I came across this thread - clearly another unfortunate customer with a nice bubble in his almost new MC-2:
http://tasmania.bushwalk.com/forum/viewtopic.php?f=15&t=18780
Well, could be worse - the bubble in mine grows even bigger at some altitude. 4000' seems enough to do the trick already.

Just the other day I inspected the latest compasses at a local store (mostly Suunto, Recta and a few Silva models). Some of the less expensive (~$20) baseplate compasses - still in their original, unopened packaging - already had bubbles! The salesman retorted immediately that a bubble has no effect on the compass accuracy, therefore is not considered a manufacturing defect covered by warranty. Which is admittedly in line with Suunto's official warranty policy, so I suppose that's the end of that.

It's a shame really, but maybe now in the era of GPS the demand for quality compasses is decreasing so much that the manufacturers can get away with inferior products. Worse yet, a lot of people have started to treat compasses as disposable items. I know a local scout leader (and a great guy he is) who buys Silva and Suunto baseplate compasses by the dozen for his troop. Most compasses don't last longer than a few years due to "rough" handling and bubbles so they are replaced without much thought (not that it's a big investment in the first place). Curiously enough, a few of those inexpensive baseplate compasses soldier on for many years while the rest fall apart fairly quickly.