The small dog side has been renovated. There is now grass and the scrubby bushes have been taken away (trees were left and trimmed). It was still locked when I last went (7/8/11) but I'm sure it'll be open soon. I'm assuming that they're similarly going to upgrade the big dog side.
I'll probably still keep going although I'm sure it'll get overrun with dog owners and their dogs who couldn't handle running on gravel. Hopefully it'll be kept clean but I doubt it.
City of Phoenix- if you're paying attention to Yelp reviews (which I'm assuming you are since you caved and installed water-wasting grass), dog/human water fountains and a dog bath station would be nice. And maybe some agility equipment while you're at it.
http://www.dogstardaily.com/free-downloads - Before AND After You Get Your Puppy by Ian Dunbar in pdf format
http://dogsintraining.livejournal.com/ - online forum focusing on progressive reinforcement dog training
http://www.youtube.com/user/kikopup?blend=1&ob=5 - videos on progressive reinforcement dog training
http://www.lifescript.com/life/family/pets/dog_park_danger.aspx - some dangers that can be found at dogparks