This isn't an employment blog, so isn't the place to examine the issues involved from an employment rights point of view.
However, the rise of zero contracts may have consequences for benefits claimants. There are two main areas where problems may arise?
(A) Will claimants be sanctioned if they fail to apply for zero hours jobs?
Will Jobseeker's Allowance claimants be penalised if they refuse to apply for work, or turn down offers for work, from employers who are offering zero hour contracts only?
According to Hansard, the answer is a reassuring 'no'. In answer to a question put by Lord Greaves on 25th April this year, Lord Freud (Parliamentary Under-Secretary of State, Department for Work and Pensions) said:
'I can confirm that Jobseeker's Allowance claimants are not required to apply for zero hour contract vacancies.' [HL6759]
Well, that is encouraging. And, in general, answers given by DWP ministers normally both reflect, and inform, practice on the ground.
However, the legal framework is a bit messy.
Until late 2012 it was very clear that there was not a problem. Regulation 72(5)(a) of the Jobseeker's Allowance Regulations 1996 made it explicit that a claimant would not be sanctioned if the position applied for provided less than 24 hours per week (or 16 hours per week in some circumstances). A zero hour contract cannot assure an employee of this, so claimants were clearly protected against having to apply for this kind of work . Unfortunately, from late 2012 onwards, new sanction rules have applied: regulation 72 of the Jobseeker's Allowance Regulations has been through some major surgery, and any reference to a minimum amount of work per week has now disappeared. There is, therefore, no explicit protection in law from being required to take on a zero hours contract.
Fortunately the lack of clarity works both ways: there is nothing in the rules to say that zero hours contracts are not a good reason for refusing a job. I also note the guidance for DWP decision makers states that they may take into account any restrictions a claimant has been allowed to place on their work search. This means it is very important that claimants try to get a minimum hours restriction included in their job search criteria, as this will make it harder for the Jobcentre Plus to argue with a refusal to work a zero hour contract.
(B) What if an employee is in a zero hours contract and it is unsustainable?
This is a bit more tricky. Again, a claimant has to show 'good reason' for leaving a job to avoid being sanctioned when they try to claim Jobseeker's Allowance. And, again, what counts as a good reason is not made clear.
Guidance to decision makers for the DWP  indicates that if a claimant knew about the conditions when they took a job but took it anyway, being unhappy with those conditions will not be a good reason for leaving. However I think it would be worth arguing against this, even if a person knew it was a zero hours contract at the outset, if they had an expectation of a certain amount of work, and this expectation was not satisfied.
At the moment we don't really know how this will develop, as zero hour contracts are a relatively new problem for most areas of the workforce, and also the new sanction rules have been in place for less than a year. If Lord Freud's statement turns out not to reflect how things are on the ground the situation will be deeply worrying: failure to apply for a job, or leaving a job voluntarily, attracts the highest level of sanction, which can be anything from 13 to 156 weeks depending on previous history.
If you have been sanctioned because of these issues, or know someone who has, please let me know.
If you want to know more general advice about Jobseeker's Allowance sanctions, have a look at my main website:
 http://www.independent.co.uk/news/uk/home-news/buckingham-palace-employs-summer-staff-on-zerohours-contracts-8739830.html (31st July 2013)
 http://www.dwp.gov.uk/docs/admk2.pdf (paragraph K2151)
http://www.dwp.gov.uk/docs/admk2.pdf (paragraph K2233)