The anti-kickstand sentiment is not completely unfounded. On bikes designed for performance, not carrying gear, a kickstand's benefits are outweighed by the cost of carrying the extra weight or the risk of frame damage by clamping a kickstand on bike frames made with lightweight tubing.
But kickstands are useful, even necessary, for certain bikes and certain situations. My rule of thumb is that for any bike with a basket or a rack for carrying a load, a kickstand is highly desirable, if not required. And for any "around town" errand bike where you'll be stopping, locking up wherever you can, and then heading off to another stop, a kickstand is a very useful. The shorter the trip and the more you carry, the more a kickstand comes in handy and the less the weight matters.
I have kickstands on all my bikes that have racks and I can't imagine how awkward loading and unloading groceries and other purchases would be without them. Since only one of my bikes was purchased with a kickstand, I had to research and decide on which kickstand was right for each bike. They're not all the same.
Standard Single Leg Kickstand

This classic design represents probably 90% of the kickstands in use worldwide. It attaches to the frame between the chain stays just behind the bottom bracket and flips up by simply straightening the bike and kicking it back. I originally had one my errand bike, until I wore it out from overloading my bike with too many groceries.
Advantages
* Available almost anywhere for less than $10.
* Some models have an adjustable length shaft so you don't have to cut it to fit your bike.
Disadvantages
* Does not fit some bikes, especially performance road bikes, that don't have space between the bottom bracket and the wheel for the mounting bracket.
* Obstructs the pedals when down, which isn't an issue until you roll your bike backwards, say in the garage or parking area.
Chainstay Single Leg Kickstand

Instead of mounting behind the bottom bracket, this kickstand mounts near the rear axle. I originally got this kickstand for my old steel road bike since it doesn't have space for a standard kickstand's mounting bracket. We also installed them on our touring bikes to handle a heavy load on the rear rack.
Advantages
* Works on bikes that don't have room behind the bottom bracket for the mounting bracket.
* Does not obstruct pedals in down position.
* Costs about $20. More than the standard kickstand, but still pretty cheap.
Disadvantages
* Harder to find, and only available in black.
* A heavier load in the rear of the bike can make the front end swing around.
* The way it sticks out in the up position is not subtle.
Double Leg Centerstand

More commonly found on motorcycles, this kickstand leans the bike fore and aft vs. leaning to one side. The two legs fold neatly to one side when not supporting the bike like the standard kickstand. I installed a centerstand on my Dutch bike due to its portly size. I liked it so much I installed another one on my errand bike after I wore out her original kickstand by carrying too many heavy groceries.
Advantages
* Supports heavier bikes and heavier loads.
* The bike remains upright, which makes it easier to load.
* Even your friends that would never own a bike with a kickstand will think it's cool.
Disadvantages
* More expensive. About $50 for the Pletscher ESGE model shown here.
* Load must be evenly distributed left to right or it will tip over.
* With more weight in the back, the front wheel flops into the frame unless you have a wheel stabilizer.
The UpStand

When it's holding up the bike, the UpStand looks similar to a chainstay mounted kickstand. But instead of kicking it away to start rolling, you remove the carbon-fiber stand from its tiny attachment tab installed on the rear wheel's skewer, gently tugging to release the tiny magnet that holds it in place. The stand is shock-corded like a backpacking tent pole, so you can fold it and put it in a pocket or bag for the ride.
Advantages
* Extremely lightweight at 40 grams total (15 grams for the attachment tab, 25 grams for the stand)
* The stand removes completely when not in use, leaving the attachment tab nearly invisible.
* Surprisingly stable, as long as you align the attachment tab at the proper 90 degrees.
Disadvantages
* It's not particularly cheap (about $1 a gram). But nothing carbon on a road bike is cheap, is it?
* The stand folds up to half its length, but you still have to stow it somewhere.
* Some of the kickstand convenience is lost when you have to dig the stand out of your pocket or seat bag.
Do you have kickstands on any of your bikes? If yes, which type works for you? If not, when would you consider installing a kickstand?