Well, the GE-SNECMA joint venture CFM gas announced that they will be working on an advanced engine for the next generation of narrow body airliner (A320 and B-737) replacements using what they call Leap-X technologies.

In addition they are teaming with NASA to apply these technoligies involved in this engine to an advanced open rotor concept (Paid Subscription Required):

It’s clearly the same no-gearbox path that GE took in the late 1980s with its “un-ducted fan”, which was killed by lower oil costs and noise concerns regarding the counter-rotating fan interaction.

The research, at least for now is about keeping the pressure ratio low on the fans to minimize noise levels.

Rolls Royce is also working on open rotor studies (Paid Subscription Required), though it’s concept is more conventional, with a gearbox.

It’s applying the EU funded DREAM research program, and will probably borrow quite a lot from the 10,000+ hp TP400 turboprop used on the A400 military transport.

One of the interesting things here is that both concepts show the same number of blades front and rear, which I think will change, because you get simultaneous interaction pulses from all the blades at once then, which means lots o’ noise.