What I'm wondering about is how Datsun will compare to Dacia. Aren't those three the main markets that Renault sells those in?
I think Dacia is largely European, to Eastern-European. You see plenty of them in France but in places like Romania, where the company was originally from, you can't move for the things.
Though I'm glad you've brought up Dacia, as it's a
vastly better analogy for what Nissan is doing with Datsun than the Toyota/Scion comparison.
Scion and Datsun would have both been created to make cheaper cars.
Scions are less expensive than Toyotas, but they aren't bargain-basement for developing markets. They're Toyotas for Generation Y drivers. As above, Dacia is a much better example. Take proven, not necessarily cutting-edge technology, and sell it very cheaply.
Most - if not all - current Dacias are based on basically the same platform - one that can trace its roots back to the 2nd-generation Renault Clio of 1998.
Renault has fantastic economies of scale on that platform, because it was making Clios on it for a decade or so, makes the Twingo now on that platform, based the Dacia Logan on it, extended it a bit and put the Sandero and Duster on it... etc. The Duster crossover, if sold in the UK, would be a good £5k or more cheaper than
any other small crossover on the market. In fact, it'd be cheaper than many B-segment cars.
I expect Nissan (given its relationship with Renault) will do very similar with Datsun - take a proven platform like the Micra or Versa, and build all sorts of different vehicles on it. Just a hunch, but they may even re-badge some Dacias.