Vincent Sarago and I tracked down and knocked out a number of tricky warping and VRT bugs last week and I made three beta releases of Rasterio. Rasterio 1.0b4 went to the Python Package Index yesterday: https://pypi.org/project/rasterio/1.0b4/. Huge thanks to all of you who are trying these beta releases out.
Releasing Rasterio 1.0 by June 31 was one of my goals for the second quarter of 2018. I'm feeling confident about making a first release candidate at least!