This isn't a recent issue and I assume that if I'd searched through more of the forums I would have found the same concern brought up before. However, I'd like to put it forward as a suggestion that the Constitution increase of a Barbarian's Rage ability could be withdrawn, and replaced instead with a pool of temporary hit-points for the duration of the effect.
The OOC mechanics of it would mean that PCs don't simply die outright when their rage ends should they take considerable damage through the fight. Potentially a Barbarian will lose more than he gains from this switch; the constitution drop will reduce his Fort save for instance.
The rational IC explanation of this would be put down to the berserker ignoring his 'lesser' wounds, instead of taking full HP damage from every little bruise.
Overall, as I play a Barbarian character this may come across as a player looking out for 'his' character, and thats partially true, but I can't be the only player with a Barbarian PC who's hesitant to use what should be an 'empowering' ability, for fear of their PC dying outright from the after-effects.