The whole parallel universe interpretation comes from quantum mechanics... so unfortunately has absolutely nothing to do with wormholes, bending space, or anything else general relativity based. This is a consequence of the fact that quantum mechanics and general relativity, while they are both the most experimentally verified theories of how things work, have nothing to do with each other and cannot (yet) be combined in a meaningful way. A wormhole to another universe would not be an 'alternate' universe in the many worlds sense, but would rather be another pocket of space like our own that is causally disconnected from our own universe (example: its farther away in light years than our universe is old and the 'space' between is expanding faster than local light speed, so nothing from our universe can possibly affect it. Except (maybe) through a wormhole or other horrible distortion of spacetime).
About FTL: the proposed drive isn't making the spaceship move faster than light - its making the space around the spaceship displace relative to the fixed stars and carrying the spaceship along. This is theorized to happen by stretching the space in rear and compressing the space ahead - and the rate of stretch/compress of spacetime is not limited by the speed of light. The math is messy and I've never read the papers describing it in detail, so thats about all I can say.
The new discovery isn't exciting because its immediately applicable, but because it radically lowers what we might have to achieve 100 years from now. The energy cited in an article I read (about the mass of one of the voyager probes) is equivalent to the energy output of the United States over about 4 years. Thats actually a conceivable amount, even if its a heck of a lot more than we can do now.
For stuff about infinity look up 'countably infinite' and 'uncountably infinite'. Its not the whole picture but really drives home that there are several types of 'infinite'.
