Given where it has already got to it is very hard to see how the OLPC could fail although its positive effects can be slowed down. Some thoughts about that:
Some Governments won't buy it. eg. There were reports in November 2006 that the Thailand government had cancelled its OLPC order following the military coup there. Happily this decision now seems to have been reversed and OLPC testing is proceeding in Thailand according to a recent report.
Some adults will suppress it. This is bound to happen but given that it will initially be personally owned by the students, mobile and take home any successful suppression would have to be ridiculously authoritarian to reverse the designed intention. ie. taking the laptops away from the children and locking them up.
Some young learners won't like it or identify with it. This will be the case for some but others will like it a lot. In developed country terms it's much more like a mobile phone than a computer confined to a lab. The Indian hole in the wall experiment shows that impoverished children learn quite a lot about computers without any instruction at all.
Other alternative technologies will turn out to be more popular. Some people, such as Keith Devlin, think that mobile phones are the answer:
Forget the $100 laptop, which I think has garnered the support it has only because of the track record and charisma of its principal advocate (Nicholas Negroponte), the ubiquitous computing device that will soon be in every home on the planet is the mobile phone. Despite the obvious limitations of a small screen and minimal input capability, with well-crafted instructional materials it will provide the developing world with accessible education in the basic numerical and quantitative reasoning skills that will enable them to escape from the poverty trap by becoming economically self-sufficient.Not sure about this last one.
It is quite hard to see how OLPC could not be successful although the quickness of uptake and degree of success will vary enormously in different regions depending on the attitudes and actions of the adults involved
There are also tremendous gains to be made in developed countries such as falling prices of laptops, increased usage of free and open source software by both developers and consumers, the example in parts of the developing world of a far superior model of computer usage in Schools and the penetration of an alternative user interface (Sugar) with a community metaphor replacing the desktop metaphor:
The mesh network is a permanent fixture of the laptop environment and is represented explicitly in the interface. A zoom is used to relate four discrete views, each of which caters to a particular set of goals: Home, Groups, Neighborhood, and ActivityAll of these things represent a huge challenge to the suffocating effects of the Microsoft monopoly which increasingly is holding back innovation and development