No, the series was cancelled around halfway through season 5. I think that's the main reason why so many characters died or looked like they might die, by the end.
There's isn't a season 6 on television. I read that they wanted to continue Angel because it was obvious the show wasn't finished. But there were scheduling conflicts and so the network decided to cancel Angel and Joss was upset about it.
However, comic series "Angel: After The Fall" continues right where season six would have picked up, after Wolfram & Hart sends Los Angeles to hell. The writer, Brian Lynch, plotted this with Joss Whedon, making it official canon, unlike IDW's original continuation of Angel, starting with Angel: The Curse.
