The change you mention has nothing to do with prior art, which is still considered when ruling if a patent is valid.

The real reason for this change is avoiding arguments over who did it first. In the past companies have gotten into huge court fights when two companies both tried to patent something they had invented a few years previously. The new rules are open to some different abuses, but they are also simple and clear cut. If the patent is issued, whoever filed first gets it.

In general these changes seem to be good for computers and electronics. Though any help to open source projects was purely accidental.

Jay