London's Shard: Love it or hate it?

Renzo Piano's Shard has sharply divided opinion amongst commentators.

The 310m (1,016ft) tapering steel structure will eventually contain restaurants and viewing galleries, where - weather permitting - people will be able to see as far as Southend-on-Sea.

The Guardian's Sir Simon Jenkins and author Peter Ackroyd give their - opposing - views of the building.