I think the boundary changes being proposed by the government could make Caroline Lucas's re-election problematic. There is going to be massive changes to the boundaries to reduce the number of MPs from 650 to between 585 and 600. An extra 6,000 electors are going to be added on average to each constituency and 50-65 constituencies are going to 'disappear' altogether! This is the Tory price for the AV referendum.
Maybe Brighton Pavilion will be one that 'disappears' and be replaced by a 'Brighton' constituency that incorporates Kemptown (without the coastal bits of Peacehaven etc). Or more likely in my opinion, seeing as it is the Tories and Lib Dems overseeing the changes, Brighton will be split into Brighton East and Brighton West both incorporating bits of Pavilion and Kemptown and more inland areas. Or maybe Pavilion will expand inland towards Lewes and Arundel creating a more rural constituency that will add thousands to the Tory vote.
It will be more vital than ever for the Labour/Green vote not to split (assuming the AV referendum is lost - the Tory 'no' campaign intend to outspend the 'yes' campaign by 5 to 1), but the Greens will have to get used to their vote being gerrymandered into different constituencies and having to campaign in more rural Tory areas to make headway.
The new boundaries are being rushed through for 2015 despite new boundaries being introduced just before the May 2010 election. Apparently political parties will have their right to appeal to boundary changes taken away from them under the new rules, and constituency boundaries will cross ward districts and county boundaries making it impossible for communities to keep track on which candidate or party is accountable in their area. All this to 'equalise' constituencies when already most constituencies are within 5,000 electors (England seat average: Tory 72,920, Labour 70,173, Lib 72,638). The new aim is to reduce this gap to no more than 2,500 electors in every seat (except in Lib/SNP seats in Western Isles and Shetland etc) - the cost to democracy will be huge.
To make matters worse, these new boundaries will be drawn on the old electoral register (over 5 years out of date by 2015) that we know does not contain 3.5 million eligible electors. Unlike at present no account will be taken of the fact that urban constituencies (mostly Labour) have 25% of eligible electors unregistered.
To make matters EVEN worse, the government also plan to introduce 'individual voter registration' which in Northern Ireland reduced the register by some 5% - this could mean another two million lost voters mainly in urban areas. This makes a mockery of the government's claims to 'equalise' constituencies - they are almost certainly going to be more unequal after this massive gerrymander is over. And the smaller parties like the Greens and potential voters even more disenfranchised and alienated.