I'm definitely the opposite of concerned - I love it. Like they said, they are only messing with things that are at rock bottom...and it's no fun to go mine iron when it's worth only 5c...and silly when copper goes for 4x as much. I really, really disliked the economy in GW1. Run a fun alliance event, best a tough dungeon, and get lucky? Fantastic - you got an item worth about 2 lockpicks. This was the case for most things, because ANet allowed people to run dungeons solo and be nigh invincible...so very few items were worth earning. And instead of fixing the invinci-builds and making Shards Of Orr tough to beat, which would naturally make Bone Dragon Staves expensive, they simply had super low drop rates for rare items. Bad form. This made them even more out of the reach for people who ran the dungeons "normally".
If people want to farm, that is fine, but it becomes an economy issue when it is (literally) 50x as profitable. The only thing I would find troubling is if they took the very rare things and made them not rare, causing a lot of people to lose money overnight.
Just my opinions, though!