Having separate words for 'her' and 'his' puts the emphasis on our differences, rather than what we have in common - which is what got us into this whole sexist, stereotyped, binary mess in the first place.
I respect the intention behind using the feminine ('she', 'her') as a way of responding to the tradition of using the masculine ('he', 'his'), except that it grates on me just as much (even when authors switch them around interchangeably within the one text). It gets me thinking about gender when gender has nothing to do with the subject matter, and it also feels more like revenge rather than a solution.
In English, it's surprisingly easy to use 'them' and 'their', but sometimes that leads to ambiguity. So I applaud this move from the Swedes.
I am reminded that Starhawk and others have attempted to introduce 'cos' into the English language as a neutral pronoun, too.