Tony Chen at the Hospital Impact blog has been keep track of retail clinics. It seems changes are afoot, with Target and MinuteClinic parting ways after two years. Also noted, Take Care Health Systems is removing their clinics from 10 Rite Aid pharmacies here in Portland, OR. From Tony's post:

So, to recap:
- money is still POURING into retail clinics
- hundreds of clinics will be opening within the next 6-12 months
- it smells like a landgrab situation, with lots of clinic operators partnering with national big-box retailers
- Like any retail business, location, location, location still applies

He's got a great prediction too - check out the post here.