Hey,
I know this is a very old thread, but Im doing Alevel English Language and we're learning about accent and dialect, so I searched 'Malvern Accent', to see what people's views were about it, if it even existed, as I actually come from malvern, and went to the same school as Cher.
Her accent isnt a Malvern one. Malvern is a very middle class area, and if you dont live in one of the main council estates around the area (without sounding horrible), then the accent is the same fro pretty much everyone.
For outsiders, the Malvern accent can be seen as quite posh, probably unmarked RP. Its very rare that people stray from standard english and say things like 'you was'.
The main feature is the dropping of 'Hs', which is replaced by an almost western sound like the Bristonian Accent. The other feature is the very pronounced Rs. The vowells are very long, which is strange for an area not in the south, but other than that, its not a very regional accent, just sounds like RP.
Hope this helps guys