"Similar game play" sounds more vague than what Irish Girl posted yesterday.
There are varying degrees of optimism as to how closely CoH can be mechanically emulated - will your level 50 with the same slots slotted while killing Skullz:
* be the same play
* feel like the same play
* feel close enough to the same play that only certain build combinations will feel slighted **
* feel close enough even though nothing is perfect but most everyone is happy
* Look, you get Paragon City back, everything else is cake.
Most likely it will be the middle three barring some documentation coming to light that I've been told doesn't exist.
This completely discounts the possibility that the 1.5 ( really not keen on that labelling ) will be City of Titans game engine, set in the CoH universe(s) which would be somewhere between the latter two on that list.
** Let's be realistic, this will happen even when the i23 servers come back up.