Most experiments that have tested Bell's inequalities, have been carried out using pairs of photons 'flying' in opposite directions. Althouhg the experiment done by Alain Aspect involved photons from cascade decay of excited atomic states, experiments done these days have overcome this problem by using photons coming from a single process. Photons or particles, like electron-positron pairs, that are coming from a single quantum process are said to be in entangled states. It is in such entangled pairs of particles that the EPR argument has been tested through Bell's inequality. Experiments have also been designed and performed, to limit any possible 'communication' between pairs of particles, by randomly altering of the conditions (orientations) of the polarisers, just a 'split' second before the arrival of the particles at the polarisers. So far the experimental measurements, of photon spin correlations done over distances of about 100Km, have violated Bell's inequality, adding credit to the power of quantum mechanical prediction. The new experiments you are refering to, make the bold step to entangle three or more particles, in which the task will be to test the three or more parties correlations. Also, a very interesting aspect of the new experiments, is that they plan to generate hibrid entabgled states such as electrons and atoms, for example. These are the new elements in testing Bell's theorem in these experiments. The results from these experiments could lead to new studies of the evolution of the early universe.