[Microsoft Surface] GoodDayToDie:
Programming languages: C/C++, VB.NET, C#, and JavaScript for the program code. Raw DirectX, XAML, or HTML/CSS for the UI. Those are the official options. Oh, and PowerShell or any other scripting language supported out of the box on Windows if you want, but you can't distribute through the store if you do that. However, the tablet has no problem downloading and running scripts.

Screen protector should be unnecessary. Gorilla Glass 2 is absurdly tough stuff; there have been instances of Surface tablets getting run over by cars and/or flung into the air with only minor damage. The Touch or Type Cover will also provide a great deal of protection.

There is nothing "to say" that the tablet won't end up like anything. You could ask the same question of the iPad, and be only slightly sillier for doing so. Nobody can see the future, and I doubt any of us here have enough knowledge of the market and have done enough research to even have a very credible prediction. However, if you just want some reassuring evidence, there's a few things: It's selling better (at full price) than the Touchpad did, it's running what mostly amounts to a mainstream OS rather than something which never did well in the marketplace, there are multiple devices running this OS so it's not a one-of-a-kind thing, MS has put a ton of effort into promoting and marketing it, the hardware design is arguably much better, I believe it has several times as many apps already, it includes support for critical formats like Office documents...

You can download MP3s, or any other kind of file. In fact, I don't even know how you think you would put an MP3 onto Surface from another computer. I guess you could use Windows networking (it can join Homegroups or use the legacy networking) or the microSD card, but... why?

It's Windows 8 (recompiled for ARM), not something completely locked down like iOS. You can also run desktop programs as Admin (it comes pre-"rooted") and can do all kinds of system stuff (change security policies, install drivers, modify partitions, edit the registry, etc.). You can run scripts, even ones downloaded off the net; I've written several (it's the easiest way to do write a small third-party utility). You have full access to the filesystem (including the admin-only parts if you use elevated permissions). Despite what iOS and (to a lesser extent) Android have been trying to teach the world, a tablet OS doesn't have to prevent the user from doing anything outside of an app sandbox.

I'm not even going to dignify your request for pirated apps with an actual response. Be grateful for that; it would consist of a considerable amount of flaming. Unlike you though, I try to respect the rules of this site (although I currently have lost pretty much all respect for you). For the benefit of anybody else who might think to (or rather, who might fail to think, and therefore) ask for such an insulting thing here:

Piracy is strictly forbidden on XDA-Developers, you will be reported, etc. Read the rules. This is a *developer* community, not a "give me stuff for free; I'm clearly entitled to other peoples' work for no compensation!" community.

Many of us have developed apps on the store. Some people (myself included) choose to make our code available on XDA-Devs for free (with source, even) as a means of giving back to the community that we have all benefited from, but if there was an easy way to exclude the freeloaders I would. As a side note, one of the other reasons that piracy is so off-limits here on XDA-Devs is that, if the site becomes known as a place to learn about or download pirated software, that will expose it to legal troubles. Seriously, just don't.