Hi,

A client of mine has a well-established site which is a .co.uk She has now decided she wants to go 'international' and move it to a .com. She has just registered the .com domain. What is the best way of moving the whole thing onto the .com without losing the Google positioning? (She needs to also redirect the .co.uk onto the .com so she doesn't lose existing clients)

Many thanks

Algorithm counts many thing such as links to the domain name, quality content, relevancy and etc. I believe the best thing is first to point the new .com to .co.uk domain and to start changing link URL to .com one. I do not recommend moving to .com at all since the co.uk one is popular and well ranked. It is better to add a small presentation under the .com name and to have it linked to co.uk

cheers

A 301 redirect is the safest way to redirect users, and bots, To the new domain.
It's likely that you will see some change in position initially though.

Does google transfer the page-rank-not-that-it-counts-for-anything-Chris-I-know of the old to the new after a 301 redirect?

yes it does (eventually)

And will the new domain be sandboxed?

redirecting from existing to new will trigger the aging delay (experience not heresay/theory)

Use a 302 redirect until the new domain starts to replace (rank alongside) the old for competitive phrases the switch to a 301.

Is Google OK with 302's now? (A couple of years ago it was a definite no, I seem to remember, but a couple of years is a long time ago...)

A 302 redirect has always been perfectly ok within your own site and from external sites. The problem was/is that given certain conditions it could create this "hijack" situation.

In this case use of the 302 is required to keep the older URIs indexed while sending browsers to the newer one. In addition your linking campaign should be for the new hostname and you should also be looking to get existing links switched over.