The indefatigable Ace links to a New Editor piece which makes a ridiculously optimistic projection that we'll achieve human immortality in 25 years.
Functional immortality is still a pipe-dream. We won't see it. Our grandchildren might.
Best we can hope for is about 140 years.
You might be interested to know we have only very recently discovered why men live longer than mice. It has nothing to do with "accumulating junk proteins"; that's a 1970s hypothesis popularized by Larry NIven's "A Man Out of Time" and other fiction, but since pretty well discredited. Why do men live longer than mice? We have protein encoding for the creation of antioxidants that slow down cellular-level damage from free radicals. Animals that live longer have more of these proteins, shorter-lived animals have fewer.
It's now believed that it's the simple accumulation of cellular damage, the result of which is cascading loss of information that all cells need to perform their incredibly complex operations, that causes aging. This cellular entropy will be very hard to fix; you're talking about a process roughly equivalent to debugging a decillion terabyte program. Oh, and the data is stored in three dimensional amino acid base pairs, and you have to keep the program running while you fix it or the person dies. Good luck.
And we're only beginning to understand how the data is encoded three-dimensionally; the supercomputer Blue Gene was built for this specific purpose. We're not anywhere close to being able to fix any of the damage. It'd be like asking a Stone Ager to fix a microprocessor.
Of course, it's far easier just to create a new organism from scratch than to continue fixing the old one in the face of entropy. Which is why nature does exactly that.