Pros
OCLC has some strong technical talent, appreciation for life outside of work, and a unique and challenging mission. Its nonprofit status gives it more flexibility in providing services and software to libraries. Arguably the scope of OCLC's mission and data is similar to that of Google (at least Google Books), but where Google relies on algorithmic classification, OCLC also relies on librarians. The result is qualitatively different than what Internet search engines can provide. It is not a company where you can be unwillingly lost in the shuffle. If you can deliver a compelling result, you will be recognized , rewarded, and afforded more decision-making latitude. Fresh technical leadership will thrive here, especially if it has expertise in the mobile development and cloud computing areas.
Cons
Product design and product management is bad. Many of the software products are given resources beyond their needs, while others are slowly starved. OCLC's nonprofit status encourages this, as the bottom-line costs and benefits of any product or project are often not given enough consideration. While the technical staff has above average competence, the demands of some product managers go so far beyond what is necessary or useful that the software developers and systems administrators find themselves overworked and far outside their areas of expertise. This leads to poorly implemented software and systems, resulting in more overwork. The field of library automation was an early adopter of computers and the Internet, so there is a strong contingent of older software and data that one must navigate at OCLC. (I didn't write "legacy" software and data because there is no indication that any of it is going away soon.)