The exact wording of the baptismal ceremony was not fixed in the first century. While I do believe that invoking the name "Jesus" in the act of baptism is probably the most primitive baptismal formula, I do not think that there was any great discussion or division over the words pronounced at baptism in the primitive church.
I do think that there was a wide range of meanings applied to the act of baptism in the early Jesus movement. The roots of baptism are in the purity washings regularly practiced by second temple Jews - rites of cleansing that removed ritual impurity and prepared the individual to join the community act of temple sacrifice. The archaeological evidence of the Hebrew mikveh - pools for ritual cleansing - at Masada, Qumran, and Jerusalem speak to the importance of this repeated Jewish practice.
Whatever theology of baptism we might embrace, it is important to remember that at its most basic level, baptism is an act of cleansing.
Proselyte baptism - a one-time act that along with circumcision and sacrifice marked entry of non-Jewish converts into the Jewish community - also played a role in the origin of Christian baptism. This act was a once-for-all-time rite of initiation, celebrating the joining of covenant community, the movement from darkness to light, from death to life.
But most powerfully - and in the most direct influence on Jesus and the Twelve - John the Baptizer reworked the Hebrew notions of baptismal cleansing into the final act of preparation for the impending coming of the kingdom of God. Baptism for John, and for the early Christians, was an eschatological moment that embraced the "world to come" which was already invading the present world in God's sovereign act of consummation.
Significantly, it was not just that John baptized or just that he baptized Jesus. The real significance lies in the fact that John baptized - and baptized Jesus - in the JORDAN. John's baptism was re-enactment of the final triumph of the Exodus, the "new Exodus" promised in the latter chapters of Isaiah where Israel once again steps through the waters of the Jordan and into its promised future.
[NOTE: The more I read the New Testament, the more I understand "salvation" - not in individual terms - but as the restoration of Israel which includes the end-time ingathering of the Gentile nations into the people of God. Individuals choose to align themselves with this coming regime and enjoy the liberation it brings or remain trapped by the powers of the present evil age.]