According to the BBC website, Battlestar Galactica has been commisioned to do another six episodes.

Over three million TVs were tuned to the cable-only channel during Galactica, giving it the second-highest ratings ever for Sci Fi. (The Stargate: Atlantis premiere, since you ask.) It even outperformed a new episode of Enterprise in several key demographics, despite the Trek ep being shown on a network rather than a cable channel.

All this is good news for Sci Fi, who had been concerned that ratings would be low due to viewers downloading the show from the internet rather than watching it on TV.

Source:BBC

The 13th and final episode of season one is aired in the UK on Sky One tomorrow night. No details on when the next 6 episodes are due to be aired.

Surprise for me. I got the impression that 13 was the lot for season one and the judgement as whether to commision another season would come from that episode run. However commisioning a confirmed six sounds like they are adding to the first season compliment.

Whether it is considered a second season or just a mid season confirmation for the second half of the first season won't be clear until we know whether they are moving straight on into production or taking a break.

Either way, it's good news for the US and the UK.