Franklin Chang-Diaz was on one of the space exploration shows (may have been The Universe) talking about the future of space propulsion. The show made it seem like this form of engine was right around the corner.
As far as current trips to Mars, I remember this from a few years ago:
Inspiration Mars
2018 Alignment with Mars for optimal window for arrival and return.
Shielding for craft of today:
Mars mission couple have to coat spacecraft walls with their own POO to protect from cosmic rays | Daily Mail Online
Shielding for craft of the future:
Scientists Designing “Ion Shield” To Protect Astronauts From Solar Wind