I've not been the Seneca Casino in Salamanca, but yea, would expect the same games. They have some CSM in Niagara for about a year, but seems like they haven't added more.
I agree a Casino there is not going to do anyone much good except the Senecas. People who visit Niagara Falls, may stop in Buffalo for a day or two but if they want a Casino will probably go to the Falls. They think their high end rooms are going to draw high rollers, but why wouldn't they just go to Vegas and get comped into nice suites?
It will only take money out of the pockets of local people, many of whom are poor already. Buffalo has a gig enough problem with lottery ticket sales in the poor areas.
I'd probably stick to Niagara anyway except maybe one visit if Buffalo opens. The games are better than nothing, but hard to take advantage of them.