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Under the bonnet

Snow Leopard saw the move to an all-Intel software architecture of mixed 32-bit and 64-bit construction, with Rosetta as a translation layer to run older PowerPC apps.

Lion is similarly Intel-only but sees another step further away from older software by abandoning Rosetta altogether, to make Lion a home only for pure-breed Intel-coded applications. It also seems to be installing a 64-bit kernel for all legible Macs. Several of Apple’s own applications await the transition to 64-bit, including iTunes, the iWork suite and DVD Player.

We witnessed some changes in the behaviour of server connections. A new SMB system has been implemented, and in our tests, we sometimes had difficulty in making connections to the Windows server in the IDG office, as well as QNAP NAS drives.

Download and installation

OS X Lion is the first operating system upgrade that Apple will not offer on a physical disc. With the help of its new datacentre in North Carolina, the company is extending its online media and software delivery services to include the entire Lion OS, all 3.76GB of it.

This is a controversial decision, not least because it means that you must have a shopping account with Apple to buy it through the Mac App Store; and if you have a minor fleet of Macs in the home or office, Apple’s advice is that you must download the hefty package to each and every one individually.

There have been hints from users who have tried the Developer Preview that you can extract the necessary .dmg file from the ‘Install Mac OS X Lion’ package, and use this to create a bootable install disc.

During the installation process, a recovery partititon is created on the Mac’s boot drive, from which it’s possible to effect repairs on a damaged primary partition.

Lion Filevault

Full-disk encryption, not just user directory encryption, is possible with Filevault in OS X Lion

Security has been tightened further in Lion, starting with the expansion of file encryption. File Vault has been around since 10.3 Panther but the move to Lion sees a new option for full-disk encryption. We tried this extra level of security on our ageing MacBook Pro, and can report no perceptible slowdown in performance.

250-plus new features

Apple lists 250+ new features in Lion. We’re still to explore some of these, most notably Air Drop, which we couldn’t test as the wireless adaptor on our macBook Pro (Early 2008) did not seem to be compatible.

Air Drop is a novel way to combine traditional wireless networking with ad-hoc wireless, which gives point-to-point connections between individual computers.

The system is designed to automatically show other Lion Macs in your local wireless zone, and let you simply drop documents into their dropbox to share and exchange files.