As the news article said, this idea has been kicked around for years. It probably could happen quickly as far as manangement is concerned, but as far as employees are concerned, I agree with BMC, there are just too many contractual issues to be worked out. There are even different unions representing some of the crafts on Metro-north, then are representing the same crafts on the LIRR.
Other major stumbling blocks would be how to handle senority issues, if people were allowed to work the entire system, and as also said before, there are completely different work rules in effect on both railroads.
If a merger happens, it will probably be on an upper management level, and not much more then that.
The metro north M-7's are allready being brought to arch street for service, I went by there yesterday on the way to NY, and saw two strings of Metro North M-7's being serviced there.
According to a transportation manager I know, back around 1990 or so, new decals were delivered for the shops in morris park that said
"Metro South Commuter Railroad" Instead of "Long Island Railroad".
They were promptly sent back. I dont know if this is an urban legend, or if it actually happened. According to that manager, it did happen.
A Side note about Conductors and engineers on the LIRR...
On the LIRR, Conductors are not promoted to Engineer if the Engineer does not show up. Union work rules on the LIRR forbid this practice which is common on other railroads.
However, if the Conductor does not show up, and no one else on the train crew is qualified, the Engineer is given the responsibility of being in charge of the train, and is given an extra days pay. This does not happen very much anymore, since in most cases, a brakeman or collector would be a qualifiied Conductor, and they are promoted to Conductor.