Having sold ourhouse quicker than we anticipated we went into rented for almost 2 years. It depends where you are, but where we are (where property is very expensive) renting was much cheaper than a mortgage would have been on a similar sized property - that worked very well for us since for a year of that I was on maternity leave which was less than my normal salary. Property prices weren't increasing at the time so we weren't losing out by being off the property ladder, the only negative (albeit a very small one) was that we were not paying anything off a mortgage, even small payments. Doing all the sums, we were better off renting.
As others have said, maintenance is down to the landlord and our house was managed by the local estate agents so the 2nd weekend we moved in, the boiler broke down and given that it was weekend, the estate agents was closed. We had 48 hours without heating or hot water in a very cold January. Apart from that however, the agents / landlord were great. It was also someone else's house, so you have to live with the decor (not a major issue) but you sometimes worry about getting the carpets dirty or marks on the walls from putting the children's pictures up.
It worked brilliantly for us though, enabled us to get to know a new area, gave us a head start when a property came onto the market that we wanted - could move straight away etc, really strengthened our position.
Tenancies are usually 6 month or 12 months, there is usually a break clause where the landlord can ask you to leave but it will only be at the end of the 6 or 12 month period.
The only other negative to add in case it affects you is that if you are in rented accommodation when you apply for school places (depending again where you are) the LEA will only consider your rental address as your permanent address is the tenancy is for 12 months or more - if it isn't, they'll class you as living at your last address.
Mandy