Collection of thoughts:
The new Army Class A’s: I like them, overall. The airborne trooper looks ridiculous with the slacks bloused over his boots. He should just tuck them in with minimal blousing appearance (why would you need to blouse your boots in a service dress uniform anyways? If you need to keep bugs out of your boots in your office that badly, you really oughta call pest control or something.)
As for the bellhoppiness of the thing… eh, they’ll make it work. At least they don’t look like they’re wearing cheap business suits with rank insignia like the Air Force’s Service Dress uniforms (sigh, I was looking forward to the new service coats. The ones that’d make us look like we were in the military for once. Alas, I understand WHY we decided to back burner that until we fix the ABUs, the PT program, the EPR system, the tanker contract…)
The Navy uniforms: The khakis? Eh, they’ll make it work. Every new uniform looks weird when they’re new. I like the black-and-tan uniforms too, lower enlisted and junior Petty Officers wearing the khaki tops is a bit strange (and not nearly as strange as the E-2 and E-3 collar pip ranks…), but at least they wear distinctly different colored pants. This way I only have to worry about getting Chief Petty Officers mixed up with Lieutenant Commanders, a chronic problem of mine…
Going shopping in the camo uniforms… basically, the rule of thumb is, you can go somewhere on your lunch break or on your way home in the uniform only if it is typical for civilians to go there in the civvie equivilant of that uniform. So if you go to a grocery store or a gas station, and it’s not uncommon for folks in coveralls or t-shirt and blue jeans to be shopping there, you can do it in fatigues.
As for the guy tucking his shirt in or not? The shirt has to be tucked in on pretty much all of the uniforms now (including the PT uniforms, a recent change in the Air Force that nobody really likes…) I think there might be an exception for thermal shirts (a sweater or a second layer of undershirt worn over the t-shirt to stay warm), but that could just be a bunch of guys I’m seeing not wearing the uniform properly. What you’re most likely seeing is the guy’s camo top (technically they’re called blouses, tops, or jackets, depending on the uniform), which is never to be tucked in, just the same as the Marine’s coat in the other picture.
Also, ahem, that Marine is not walking a dog. He is escorting a Marine NCO during a parade. Don’t worry though, at first glance, it’s easy to mistake a Marine for a bulldog. The key difference is that bulldogs are more subtle and eloquent in communication.
And yeah, in modern (general) terms, Cavalry is anybody who rides into combat. Used to be done on horses until they went out of fashion, later they added jeeps, tanks, Armored Fighting Vehicles (think the Bradley and the Striker APCs), and helicopters to their arsenal. The thing is, I believe they’re only cavalry if they typically fight from those vehicles. If they ride the vehicles TO the battle, then get out to fight on foot, they’re Mechanized Infantry or Airborne/Air Assault (Airborne fall out of airplanes, Air Assault fall out of helicopters. Either way, the general idea is to fall from the skies to generally tear somebody a structurally superfluous new rear orifice.)
Sometimes a unit will get called one thing when they do something else, because they are traditionally a certain kind of unit. For example, the 101st Airborne Division, which has not had any paratroopers for a long time.