Sport & Product Design  

Well I love cycling and...
Well I love cycling and after big legs and good lungs (and, uh, 'vitamins' if you're a pro) bike design is pretty important. Frame geometry, materials, gear systems etc are all constantly evolving. Gear shifts in particular have improved enormously over the last 10 years.

The Athletic Cup has always seemed wanting as a design...
though I think the sports bra (which as a man I do not wear) seems a great design improvement.
Most boats are designed for sizzle and not steak. But some of the great old boats like early 1970s Bertram sport fishing boats and very early Boston Whalers are being rediscovered and re-expressed in modern designs. Also, as I learned from Koen, roto-moulded and polypropylene boats are leap frogging old materials in many ways.
Staying on boating for a second, the lowly jon boat brought from France to America by French fur trappers in the 1700s, and which nearly became extinct for awhile, have been rediscovered and are now being built in sizes up to 20 feet that are probably now some of the best designed and most useful boats on the water at any price. And aluminum welding instead of rivets makes them leak free.
Fishing and hunting clothes have IMHO hit a low tide of style and good looks. Red neck chic rules. The only real progress involves introduction of some of the computer designed camouflage patterns developed in testing for the military that do make hunters harder for deer to see, but why in hell are they out shooting deer anyway?
Formula One racing cars have always appealed to me as great design/engineering.
Snow skis improved dramatically with parabolics a decade or so ago, but then stasis has set in. Ski clothing changes for the sake of change and not for the sake of improvement, either in function or aesthetics of late.
Basketball uniform aesthetics and cuts change frequently and are currently manifesting a prison body/tough guy chic that expresses how rough the game has become.

Baseball uniforms seem kind...
Baseball uniforms seem kind of an aesthetic mess to me right now, neither effectively breaking new ground, nor effectively achieving a retro look. The two best baseball uniforms remains old NY Yankee uniforms and old Brooklyn Dodger uniforms and maybe old Detroit Tiger uniforms. Progress in baseball uniforms' appearances peaked in the 1950s. Synthetics have made them cooler, but never better looking.
Football, especially NFL football, uniforms are, except for the most traditional, are just plain hideous. And it is not that I love the old and don't want progress. I yearn for new uniform designs that are not vapid.
Men's racing swim suits have really improved by getting away from the Speedo cock band aids that were worn for so long. Think Michael Phelps recently. They cut down water resistance and look fabulous, at once retro and the same time futuristic.
Women's running suits in the sprints are awesomely sleek and good looking and have been for a couple decades now (since FloJo anyway).
Women's tennis suits have fallen into a grotesque awkwardness. Here the Williams sisters are these fantastic, almost unprecedented physical specimens and it is as if the designers can't figure out any thing elegantly fitting to put them in; this is a design crime.
Rugby uniforms are frozen in time.

Soccer (futbol) uniforms at...
Soccer (futbol) uniforms at the children's levels are really bad--tacky--K-Mart green light special stuff. I don't know about the great professional soccer teams and their uniforms, because I don't follow the game.
Skeet shooting clothing, which once used to combine the best of safari clothes and English shooting attire, has descended into Special Ops chic.
Safari clothing of the Hemingway era is still fabulous looking, but only if you can find some old Willis and Geiger on Ebay. The new stuff is made too crappy to be serviceable in the boonies. No matter. New or old, the style, though beloved by me, is now too cliche to be worn on actual safaris without being ridiculed by the other blood thristy sons of bitches in the hunting expeditions, who dress more like mountain climbers and back packers than hunters.
Mountain climbers and back packers have fared well. They have embraced all the latest fabrics and, when they are not overdoing color, look and feel pretty good.
I haven't taken a look at curling, so I can't say what they're up to.