I know that not everyone likes to talk about taxes but Kevin C. Gillen, Ph.D. and John A. Westrum wrote a Case Study that analyzes the impact of the 10-year tax abatement. Philly Biz Journal's summary can be read
here and there is a link to the case study on their page. The Case Study focuses on Brewerytown Square which was an 144 market rate townhouse development completed from 2005-2010. The developer was Westrum Development Co which is owned by the co-author of the Case Study so there is a lot of financial information that is not normally available to the public. It is an interesting read.