Quote Originally Posted by Suetonius, Vita Claudii, 25.4
Iudaeos impulsore Chresto assidue tumultuantis Roma expulit.
Quote Originally Posted by My (very literal) Translation
He [Claudius] expelled from Rome the Jews, constantly causing disturbances, with Chrestos as the instigator.
With respect, Sigurd, I would suggest strongly that the Tacitus passage, no matter whether the individual letters, mentioned in the article you linked to, have been changed, would still indicate that there were Christians in Rome in AD 60. Certainly 'Chrestos' could be a title, but given the context and the details (killed by Pilate etc.) which do not seem to have been interpolated, it seems reasonable to accept the Tacitean account.

TR. Re: the Josephus passage, you are correct that there is no documentary evidence that it was interpolated. This is because all the manuscripts which we have are later copies, made by church historians. It seems likely that this was an early insertion, long before the first surviving manuscripts. There are numerous details in the Testimonium Flavianum that render it highly unlikely that it represents Josephus' view, though the original notice may well have mentioned Christ.

Certainly I would not deny that Jesus probably existed and preached in a manner similar to how he is portrayed in the NT. That said, though you keep saying that denying Christ's existence is akin to denying Abraham Lincoln, we have much more contemporary evidence for the latter's existence.