YBCO is not new, but the production of it in the amounts and quality necessary for large superconducting magnets is still difficult. You need to produce long stretches of the material to create large magnets efficiently, and that isn't trivial.

The old superconductors typically used in this kind of magnets have been pushed to the limit already in Nuclear Magnetic Resonance, ~23 Tesla is the strongest existing commercial one and this seems to be a limit for that technology. The first NMR magnets that use YBCO are expected in the next years as far as I remember, I don't think any exist yet.