This passage occurs as a New Testament Lesson in the RCL "Pentecost"/"Ordinary"/"Proper" Season, Year A, most recently September 2014. It also occurs at other points in the Lectionary, including Palm Sunday.
This is a very rich passage. By itself it stands as one the most powerful description of Christ and his work. Worth pointing out though is that Paul continues to build off the imagery the rest of his letter to discuss not simply Christ's work on the cross, but also Christ's work on us. He changed his shape (μορφη) into humility but will co-shape (συμμορφος) ours into glory, not simply through his suffering, but even our own.
μορφη ("shape" or "form"; 7, 8) If you look up this word, you will find it appears twice in Philippians, once in verse 7 and once in verse 8. Jesus had the form/shape of God; took the form/shape of a human. Sounds good. However, later on in Philippians, Paul comes back to this word, but using it with the prefix συν (the -n becomes a -m...see note below) . First, in verse 3:10 where he says that he is being συμμορφιζομαι-ed into Christ's death and later when he is being συμμορφος with Christ's resurrected body (3:28). Paul moves from talking about the form of Christ to the co-formation of the believer, both into suffering, death and then resurrection. I think the word μορφη can be used to guide one's reflections on the whole letter: The transformation of Jesus creates the transformation of the believer. To put it another way, I see Philippians as Paul's personal exposition on his line in Romans 8:17: If children, then heirs, heirs of God and joint heirs with Christ -- if, in fact, we suffer with him so that we may also be glorified with him.
εκενωσεν and κενοδοξια ("emptied" from κενω, 7; conceit, 3) Much is made from κενω, which means to empty. I find it interesting that Paul gives warning just a bit earlier about conceit, literally false glory. The only way to true glory, for Christ and for us, is through suffering and death.
κατεργαζομαι ("work out", 2:12; from kata (intensifier) and erg-oo (to work)) One possible meaning for this verb is simply "achieve" but another one is "to work up," ie, to make use of; fields, for example, are worked on to make them ready for harvest. This verse can be problematic in that it makes it sound like our salvation is our responsibility. However, Paul's never verse, 2:13, makes it clear that God is the author of our salvation. I think in this case, Paul uses salvation (σωτηρια) to describe our entire relationship with God in Jesus Christ, specifically the process of dying and rising. It is worth noting that the verb here (and also for "co-form" (see above) are in the present tense, suggesting this an on-going process.
Grammar/translation: The morphing "n"
When someone learns Hebrew, they learn verbs like n-t-n, which means to give. They then try to read these in the Bible and discover it hardly ever exists in that form and most often the "n"s drop out in conjugation so that words like y-t-l-m mean he gives or something like this. This is true in Greek, but in a different way. The problem is not Hebrew, but the letter "n" which has a soft sound. It tends to morph into other sounds. This actually happens in Latin. For example, con is the prefix for "with" But notice how often that "n" disappears or morphs: communication, cooperation, combat, comfort, command, corroberate. This happens in Greek, especially when verbs add the prefix συν. The weekness of the "n" sound is also shown in the fact that its moveable (ie not very necessary).