Windows 10 will NOT be a free upgrade for software pirates. Unless you got your pirated copy with your PC.
Microsoft is continuing its weird piracy dance where it wants as many people to pay for Windows as possible, but would also rather have those pirates use Windows than someting else.
So Microsoft put out a very finicky, slightly tortured blog post on the topic las week. The official word is that people running pirated Windows 7 or Windows 8 devices will get some "very attractive" upgrade offers, which might be paid. But if you're getting them from your PC maker, they might be subsidized so heavily they would be free. If you're in the U.S., you may not be familiar with PCs that are actually sold with pirated Windows, but in other countries it happens all the time.
Reading between the lines, it also sounds like Microsoft isn't going to be *too* aggressive at cracking down on Windows 10 pirates, although they'll be stuck with an embarrassing desktop watermark flagging them as pirates.
In other words, nothing's changing. PC makers pay for Windows. We're talking billions of dollars here. So Microsoft can't really make Windows free. Microsoft really wants everyone to be running Windows 10 to avoid the years-long split we saw between Windows XP and 7. And Microsoft wants people in China and India, where even the OEMs are sometimes pirates, to run Windows. The uptake here is that whatever your situation, there will probably be a Windows 10 for you.