I've been looking into the different options for setting up a UK bank account before I leave Aus since everyone says its easier to set it up before you arrive. The 2 options I was looking at is using 1st contact as I've read a lot of people here used them, or setting up an HSBC Passport account. Has anyone done this with HSBC? How easy/helpful were they etc? Is there a different account with HSBC that is available to people moving to the UK that is better than Passport? I won't have proof of UK address until I get over there, and haven't oranised work there yet. Also I'm pretty sure you don't get a credit card with HSBC though and you can apply for one with 1st contact, is that right? For anyone that has used 1st contact to set up a bank account, what bank and type of account to they set up for you?? Sorry for the stack of questions, just hoping someone whos been through this before can lend some advice!
Personally, I would go for 1st Contact because not only will they organise your bank account (probably with HSBC) they will also give you information on where to live as well as other important information such as how to apply and get a NIN (National Insurance Number) which is something you need by law when you work in the UK.
You cannot apply for a credit card until you have lived in the UK for three years, soon (because I tried to get a cc recently) the law will change to reduce the limit to 2 years. They check your residency by checking your proof of residency against the UK electoral roll. You can however apply for a VISA Debit, which is like a credit card - but with no credit. The advantage of this is you can use it for on-line purchases and other credit like purchases.
I have friends who have used 1st Contact and they said they were very good, took a lot of the hassle out of it all. I on the other hand did not go down that path and learnt everything the hard way. While it is still possible to do everything yourself, even without utility bills for proof of residency - I would recommend 1st Contact (or similar service) if you can afford the expense.
Whatever account or bank you decide to go for, make sure you read the fine print - ask the bank what catches there are with the account. Some accounts require a fixed term contract so that you're locked in, others require a minimum amount of cash in the account (or they'll charge you service/account fee's) and some have a low maximum withdrawal per day.
Anyway, good luck!

We opened an HSBC account via Travelex. Just like you, we had no proof of address or no job lined up before we left. We've experienced no hassles whatsoever, as long as you give yourself enough time for the processes. We were told it would take 6 weeks for the paperwork to be processed, but in practice it took a few weeks longer. A week before departure we still had not received the relevant paperwork from HSBC (accountnumber, BSB no etc) and were getting a bit nervous. We spoke to our contact at Travelex who offered to ask HSBC to fax us a confirmation of our account details. Within 24hrs we received the requested fax.
Then once in London, we went straight to the Regent St branch where we were given the debitcards and all the paperwork. We were also offered the chance to apply for an HSBC creditcard with a credit limit of £500, which we did. I think a week later we had them in the mail (you can also opt to collect them from the Regent St branch).