Dunno. Tritium half life is 12 years and ~19keV per beta particle so
with the right ideal converter you might hope to get 1000 electrons at
18v per disintegration. But to get laptop powering currents out of it
would require a quite alarming level of radioactivity inside the
battery. It is a hoax see for example:
http://gadgets.boingboing.net/2007/10/02/30year-betavoltaic-b.html
(and more than a year old too)
Apart from the radioactive source powering the thing it is non-nuclear.
Useful in some remote low current applications like spacecraft maybe.
I suppose in the news silly season we have to expect this sort of thing.
Tritiated plastic emergency lights and fishing floats are real enough
and use the same basic technology to power them.