If there is to be a move to preferential voting, it is virtually certain that the Labour cabinet will propose Alternate Vote (a system used in Australia) or AV-plus-top-up, as proposed by the Jenkins Commission. (It should be noted that pure AV, although giving the appearance of choice, does not promise a proportional result; in fact, it can distort more than first-past-the-post in some circumstances.) Neither of these systems challenges members in safe seats, which is surely one of the outcomes the UK public is calling for.
Several bloggers have remarked on the coincidence of outrageous claims against MPs expenses and the safety of their seats. It is a point also made by Vernon Bogdanor in an interview by Lawrie Taylor last Wednesday discussing Bogdanor's new book, "The New British Consitution". In this, he throws out many ideas for democratising Britain, and shows that they work elsewhere.
One idea is "open primaries" on the American model, where registered voters at large can choose before an election which candidate should represent a party, not leave it to party committees behind closed doors. This would help to break the perception of a safe seat being a meal-ticket for life.
I believe that open primaries are not necessary if the country adopts the Liberal Democrat preferred system of election, Single Transferable Vote in Multi-Member Constituencies, but would be essential where the voter has a restricted choice on polling day.
Bogdanor proposes that the voting system should be chosen by a two-stage referendum. (He is favour of referendums where there is a major constitutional issue.) First, we should decide whether to stick with the existing system, or replace it with a proportional one. Then, if the decision were made to change, we should be allowed to choose between the systems on offer. Don't underestimate the public's understanding of these matters, he says; New Zealand changed their electoral system this way, and the change has proved successful.
Bogdanor should be a member of Brown's Commission.
Make Votes Count has joined together with a broad range of civil society organisations and individuals to call for a referendum before the next general election to change the way we elect our MPs. For more on the 'Vote for a Change' campaign, see http://www.makemyvotecount.org.uk and http://www.voteforachange.co.uk