I am planning a trip to CO over the 4th of July, including some hiking in the San Isabel NF. I called their HQ today, and they are OPEN for hiking, at least for now.
Be advised that you will likely not be allowed a fire, possibly even from a camp stove, but the trails are open for hiking.
Rio Grande NF is also open. Some of their areas are reportedly open to day hiking only; no camping. Since my trips are all day hikes, I couldn't tell you what if any areas are closed to camping.
Both NF's did warn that things could change. I guess if any more Forest Rangers set the place on fire, we might see some total closures.
Interesting - for all of the publicity about "only you can prevent forest fires" and all that stuff, the two biggest fires of the last few years, Los Alamos NM and the current CO fire, both were started by supposed professionals being brain-dead.