In terms of news themes, I like quite a few British ones...
The old Spotlight theme (pre-generic look)
London Tonight (1993-2000)
NewsBreaks (Central East/West circa 2001)
North East Tonight (current)
(BTW who composed the old LT theme and the current NET theme?)
As for American news themes...
Gari:
NewsSeries 2000/ 2000 Plus
The One and Only (earlier versions; the newer versions suck)
Great News (the original Sky News theme)
some cuts from Eyewitness News
KYW New Millennium
Image News
615:
Impact
some cuts from Alive and Right Here Right Now
Arnold:
Elevation, Fusion, Signature (somewhat), Counterpoint (somewhat; and more or less because it sounds extremely funny to me)
The themes I hate the most:
Stravinsky and Wall to Wall News (both by Arnold)
Most anachronistic theme to be used in the 21st century:
Move Closer to Your World (Al Ham): still used on WPVI Philadelphia after 30 years