Ok my perspective on the possibilities and the factors working for and against them:
I think we can probably rule out Mark and Thom who have been mooted - I've got a feeling that Thom is another Ramps and that his latin will be way better than his ballroom also he's cute and people like Iveta (although as discussed I am not sure how much influence pro fanbases have on this). Mark is probably good enough to avoid the DO - and he's likely to be entertaining enough to be memorable also hacking Len off is a good move people tend to buck against being told how to vote by the judges.
Right:
Tim - he's a character which could work both for and against him - I rather hope it isn't him because I like him but I can see how some could find him irritating - could get votes from the older generation some of whom might watch Bargain Hunt - I'm not convinced how much pro dancers votes count for but Natalie is popular and more significantly they seem to get on well - good chemistry (not necessarily of the lets all throw rocks at Kristina variety) helps a partnership probably a major factor in the Cola win of series six - these two won't get that far they'll be lucky to make it half way through the competition but it may well ensure they aren't the first boot. Also Tim may not be good but he is entertaining - this year's Hairy Dave perhaps which may work against the general trend of late for the older dude to be the first boot.
Greg - has no chemistry with Ailona whatsoever and is unlikely to benefit from any support she has which has to work against him - many on here self included think he comes across as a twonk but "Masterchef" is popular so maybe some members of the general public like him - much depends on how he is percieved by the public - the younger members of the audience won't like him - if he dances better than that will improve his position on the leaderboard but sometimes as my mum likes to point out the middle can be the most dangerous place to be - many shock exits come from that zone - and they are by no means rare in the first eviction week as people concentrate on saving favourites further down and the fact he's not as comically bad as Tim may actually work against him
Judy - hmm - several ticks against I'm afraid - age I'm afraid SCD voters don't tend to follow Jarvis Cocker's advice and help the aged unless they are particuarly flamboyant or unusually talented, she's a tad serious too - SCD voters aren't sympathetic to the nervous, her son isn't doing that well at the moment so we won't get a boost from that, the 'yes' stance of offspring could work both for and against her, I'm not sure about the supposed strength of Anton's support - he has been the first pro out before and some of his partners haven't lasted long in the competition but I guess it's more likely she last longer with him than without - my guess would be DO survivor but I could be wrong.
Scott - definately in danger due to complete lack of ability going by what people are saying about training footage (I thought he might be better at ballroom - looks like I'm wrong) but much depends on support - the older demographic won't care about a Radio One DJ - the younger may not be enough to count - DJs don't tend to do well in the vote but he might be bouyed by ah-bless vote for the bottom placed contestant. I think he seems like a nice guy but in a situation where people vote for you rather than against you - it might not be enough to get people jumping for the phones also sad to say there are homophobic a-holes out there. Pro vote - again she's certainly memorable but a few on here find her annoying and don't like her chereography she's also new which unless you have really great rapport with your celeb - aka JS/Kris, Iveta/Mark can mean you haven't already got people behind you. Joanne obviously gets on well with Scott but it isn't quite at the ah-bless level which will get people voting.
Jennifer - Mrs Brown's Boys is very popular and that may well help her - older woman tend to do better than you might expect I think a lot of older ladies watch SCD and indentify with them - she seems bubbly and has a connection with pro although he is new which will mean his support isn't perhaps quite so established. The Oirish pairing gimmick could work pro or against her - I think it will work for her because it will make her more memorable. I thought she might do better in the ballroom but those who saw her training footage think not so she may well need the help.
Suneta - if people are saying the training footage isn't great then she's in danger of the DO although I doubt she will come up against someone that the judges will save rather than her. I think she's likely to end up being someone that people forget or aren't bothered about enough to vote for on the whole Casualty/Holby City actors don't tend to get the votes and I don't think Brendan's support base is high enough to conteract this. I would be surprised if she's the boot - it will be a one week blip which will be over-riden the next week but unless she is very good I fear she may not be long in the competition which is a shame as I kinda of like her and think her and Brendan are nice partnership.
My guess would be the DO will be two of Judy, Scott and Greg with Suneta being a outside possiblity - with Judy being saved by the judges who seem to be treating her kid gloves compared to the others. I think Greg will probably be better than Scott - so depending on if Judy ends up in the DO which I think she will it'll be either Greg or Scott who goes home first.