Look here:-
http://www.flyertalk.com/forum/star-...post-here.html
http://www.flyertalk.com/forum/onewo...help-here.html
Do not over look AS - a good ffp for many it has many airline partners
http://www.alaskaair.com/content/mileage-plan.aspx
Air NZ is a terrible ffp now. Many people here on FT are looking to leave / have left Air NZ for other Star Alliance FFP's
Generally upgrades are only available on your ffp airline flight numbers and your ffp airline aircraft. Not on codeshares or other airline partners. But there are exceptions [The fine details of ffp's are not simple]