I'm an IT Project Manager. I've worked my way up from software development, through the business analysis route. I often say it's the best and worst job in the world because there are such highs and lows.
DewDr0p's post has my role pretty much summed up, however there is also a lot of technical understanding that's required in my role too. I'm not sure how much of the "widget making" work a normal (non-IT) PM would be expected to know about, but in IT you do need an understanding of how the systems that are being built works. I've worked alongside PMs that came at the role from another angle and it's generally been a miserable failure (such as they'd been with the company a few years so knew the department or users well, and suddenly management decided they could lead a project to time, cost, and quality tolerances
).
You wouldn't get hired in my team (a Programme Managed Office, private sector) without formal training. In my case, that's a degree, 4 years in IT, 2 years in the PMO function (as a business analyst), then a masters, then PRINCE2 (to the higher level, Practitioner). There is one guy who works here that doesn't have a degree, but he does have PRINCE2.
However, DON'T let any of that put you off - it's been a slog to get here, but it's fantastic in terms of benefits like salary, working conditions, and very flexible. I've worked for my current employer (permanent basis) for 6 months, but if I wanted to I could go back to freelance, there are lots of opportunities for good PMs if you tick all the recruitment boxes and can get access to employers in your sector.
I couldn't, for example, move oop north and get a similar role, because I'm too tied to large IT positions - I can only really do my job in about 4 or 5 cities in the UK. So there's that downside, too, I suppose.