Widnes yes in the short term and Fax maybe also in the short term. The question for me is what do they do for RL in the long term. Barrow and Leigh definitely not.
The problem for the RFL as they seek to grow the sport, though grow maybe an over ambitious statement, perhaps maintain might be a better view, is that the game as a limited geograpical spread at elite level. This limited spread makes it less attractive to sponsors and also allows the national media to give it limited exposure. Whether the latter is fair is something that can be debated however, the limited geographical spread is a strong justification and one that is factually correct.
The last 40 years have seen the erosion of RL within the old Lancashire boundaries and in particular around Manchester. A quick look at the league tables show that Swinton, Rochdale and Oldham are virtually dead. Salford have been on life support for a number of years. If RL can not maintain a strong thriving presence in Manchester then it really is signally the fact that it will never be a national sport.