The Universal Indult will be Rome's solution to the "SSPX problem" without Rome having to actually admit that some of the SSPX points were valid.
I doubt he will lift the excommunications. Too soon after JPII's death. It might be seen as some kind of assent to the claims of SSPX adherents about the whole Lefevre affair.
The new mass and the indult mass are not valid because they lie on the consecration of the chalice. If thye were valid, they would be a sacrilege.