Yes, it is expanding but research today shows that it will likely contract some day - once it reaches some limit, it will begin to contract into something the size of what it started out as at the big bang (I've heard comparisons to the size of a human pupil at time 0). Then once it recycles into what it began as, another big bang will restart the process of expansion. The basic elements will once again form random interconnections with one another - interactions that will likely produce a type of synergistic quality in its output at some time, some point and at some where.
If we accept the reality of multiverse, and the expansion-contraction law, there are many universes with varying proximity between them. Some are expanding (like ours) and some are contracting (like ours will do). Could some be pressed against each other, helping one contract as the other expands? Does empty (i.e. dead) space even exist between universes? Could tangible existence be approaching infinity with a dynamic multiplex in a never-ending sea of universes?
And then my only point in the post above is if there is some of calculating the maximum size the universe could achieve, since we do a bit about the rate of its expansion. Just a thought...