There is a certain type of person who, when presented with a given scenario, will instantly jump to the boundary conditions and edge cases to try and probe the limits of what he or she is facing. This, I think, is why discussions on immortality - even the colloquial meaning of "vulnerable agelessness" resulting from a way to halt or reverse the aging process - have a way of slipping into discussions of cosmology: the life span and end states of the universe.
Personally, I'd hate to be put in the position of having to make any sort of long term plans based on cosmological certainty today. The field has been in the throes of tremendous change for the last twenty years - brought on by expanding computing power and new observational technologies - with no signs of letting up soon. Today's balance of competing models for the far future of the universe is very different from the consensus five years ago, and it will no doubt look just as different in another five years.
So discussing cosmology in the context of long term plans for transhumanist-style ageless physical immortality - worrying about risk functions, how to reduce accidental death rates to miniscule levels, reengineering the body and mind to support vastly longer life spans - isn't really a serious activity in my mind. Sure, it's fun to talk about it, but it's a form of escapism - just like avoiding the topic of death and the present fight to cure aging. Cosmological research, society and science will undergo amazing, accelerating advances and changes in just the next century ... but none of us will be around to see the end results if we don't ensure that the first steps towards effective healthy life extension and the defeat of age-related degeneration are taken now.
By all means talk about these things, but first things first, folks. We have a lot of work to do before we'll need to worry about cosmological changes interfering in the continuation of our daily lives.