So, a great deal has already been said about your reasons for concluding that "transhumanism is a religion," and I don't think I have anything especially useful to add to that discussion.
I'm curious, though, as to why it matters.
That is... OK, suppose I accept your reasoning in its entirety. (I don't, but never mind that for now.)
That is, suppose I accept that soi-disant transhumanists who endorse certain texts (#10) and believe in an upcoming singularity (#9) and wear identifying symbols (#8) and dismiss those who disagree with them (#7) and believe it may become possible for human minds to join with a superhuman AI (#6/#2) and believe it's theoretically possible to extend human life and/or consciousness indefinitely (#4/#5) and to reconstruct human consciousness from brain cells (#3) and that they are better able to see the truth of these things than most people (#1)... suppose I accept that they are, by virtue of those things and those things alone, a religion.
To put this another way: suppose I accept extending the set "religion" to accept the intersection of those things.
What interesting consequences follow from my accepting that? Why should it matter?
First it should place such statements about other religions on the same level as Gnostics calling everyone else unenlightened for worshiping the Demiurge.
Second, it should call into question the statements that religion is irrational and that those that follow this are more rational than anyone else
Third, Everyone should be aware of this in order to realize that these beliefs are biasing their assessment of other peoples rationality and capabilities.
Fourth, Transhumanism should be treated by society in the same way as any other religion; That is it shou...