Peter,
you don't necesseraly need to migrate from TDP to LDP in your core in order to run EoMPLS. TDP could still be used for the IGP label exchange and LDP for the VC label exchange between the PEs.
To answer your second question, yes "tag-switching" ans "mpls ip" are the same. "mpls ip" is just the new cli.
Hope this helps,
Harold Ritter
Sr Technical Leader
CCIE 4168 (R&S, SP)
harold@cisco.com
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