re: Humphrey
It's thought to be bonneville ejecta, and thus worth spending some time at.
Although - I share your frustation in the lack of geographic progress they're making - it is very easy to forget, tomorrow marks 2/3rds of the Spirit primary mission. The Southern Hills are looking further and further away all the time - although Spirit does seem to be 'aging' a lot better than Opportunity which is suffering from the stuck heater.
Doug