The UK implementation of the WTR requires that (full time) works have a minimum of 28 days paid leave (including the Bank/Public holidays - of which there about 8).

Contract normally specify the paid leave excluding such Bank Holidays, so will be a minimum of 20. It is only the days above those 20 where the employer is giving one something extra.

Err, what? The company I work for (in the US) has like 13-14 paid holidays, and recently gave everyone an extra 3 days off right before the New Year. I think we probably have one or two more than average, but not by that much.

It doesn't, so yeah standard is 33 days including bank holidays. How many are there in the US?

Why would you include national holidays into vacation days? National holiday is more like an extra sunday. You can't move it for example if you're on a medical leave through it.

I worked for a company in the UK who allowed the option to work on Bank Holidays and take those days in lieu, was great way to actually get some developing done without the constant interruption of working in an open plan office.

You can't move it, but you do get paid. So it's worth something.