While the TNIV has received many insults hurled at it and those responsible for it, comments have mostly been over some the gender-inclusive (or gender-accurate, etc.) translation and not other changes.
The NIV has a glaring translation problem that has annoyed me for years now: the mistranslation of the Greek word for "sign" in John's Gospel. The NIV consistently translates this word "miraculous sign". However, it has been demonstrated (if you think that is too strong of a word, then how about "seriously cast doubt upon") that the word does not refer to the miraculous in John's Gospel. Praiseworthy is the TNIV for correcting this error and simply translating "sign" as "sign" and understanding John's use.
Now, regarding the gender-inclusive stuff ....
just kidding :)