Currently, the what's new content in the gallery is in the pyplot section of the gallery, I think because they somewhat (but inconsistently) use the pyplot api and are from the 0.9X version releases.

For discoverability and to really highlight the new features, it might be good to factor these out into their own section in the gallery and then add plots from more recent Whats New for the newer releases:

• Whats New 0.98.4 Legend
• Whats New 0.98 Fill Between
• Whats New 0.99 Axes Grid
• What's New 0.99 MPL3D
• Whats New 0.99 Spines
• Whats New 1 MPL3D