*cracks knuckles* well now, this has been a read. Ahem.
First off, for those of you still touting Micro SD and removable batteries. Micro SD is a thing of the past, it slows down the phone due to the horrible file transfer speeds of Micro SD, and Micro SD cards can cause crashes and other issues with the phone it wouldn't otherwise have, such as if your card becomes corrupted or encrypted. Removable batteries are not as good of a value as an external battery, where you can generally get 3-4 charges out of for the same price and can charge multiple devices. The HTC One uses a new Lithium-Polymer blend for it's battery AND HTC has disabled Qualcomm's quickcharge and made other tweaks to reduce the degrading of the battery over time, meaning that the internal battery should be good for most users for 4+ years. HTC has never had cheap batteries in my experience, and my Nexus One is still going strong after three years with an average of 2-3 charge cycles / day (incomplete charge cycles) and the battery capacity is still at 78% of it's original charge. Samsung batteries in my observation have never lasted nearly as long.
Next; build quality. The Galaxy S3 has far too much flex to it by what I've felt. My old nexus however has survived a number of instances where it's rigity has been in it's favor, such as my father trying to crush it, being tossed out of a moving vehicle on the highway, and dropped in excess of 1,000 times. Flex can help in higher impact force drops, to be sure, but it also means the internal ridged components will take more damage over time with weaker drops than if the outer shell is more rigid. I would rather my casing be dented multiple times (like is in the case of my Nexus) , or even a cracked screen (which is usually among the most easily replaced components), than having a cracked PCB.
Third, storage. If 25GB (usable) is not enough for you on a phone, then I have to ask how much of your media do you watch or listen to on a daily, weekly, or even monthly basis? Sure you can complain that you can't store those one or two movies you'll watch -maybe- every two months or so, but if you can't find a 3g/4g signal or wifi at those times, well, watch something else. Honestly, those rare bits of media that are usually that compel someone past normal amounts of data are pure wants and nothing near a need, and should be less of a priority than a durable or comfortable to hold device in my opinion. If you think it's so bad you have to make that compromise, there's the 64GB developer version or you can go over to T-Mobile or Sprint with their Unlimited 4G. If those aren't enough for you and you still want more, I'm sure there are starving children in Africa who would love to hear your first world problems.
Fourth, screen. HTC is the only Android manufacturer I am aware of that properly attempts to calibrate their screens for real-world color reproduction. Samsung over-saturates the colors on their AMOLED screens, possibly intentionally for that 'pop', which unfortunately causes a cartoon like look and in my opinion, ruins media consumption as it changes what is intended to be viewed. If you want deeper colors than is reality, I guess that's your business, but I'm not sure why you'd want that.
Fifth, Camera. HTC's ultrapixel camera is perfect and utterly amazing for internet uses and sharing with friends, close to crap for professionals who plan to print the pictures on a large size.
sixth; software. Most of samsung's "innovations" and features are already available with the core Android OS or through 3rd party apps which are free to use. HTC comes with more basic software but doesn't try to flaunt anything about the software except for blinkfeed which is perfect for the facebook/twitter crowd. The only thing Samsung has here are the air gestures in the S4, which likely will drain battery and not be used by many consumers given that they'll be more comfortable with actually holding the device for a better view and hence touching the device.
Seventh; Marketing. Samsung is one of the largest multi-faceted corporations on the planet, and has a huge marketing budget. HTC only has smartphones and has a very small budget in general, most of which goes to design. Which do you think has a better chance of getting consumers to hear and be hyped about a product without research?