Thanks for your comments, chums.
One big difference between the NPPL and the JAR/FCL PPL is that you will only be able to use the NPPL in UK, day VFR conditions. Anything more and you'll need to upgrade to the JAR/FCL PPL.
The NPPLSC will be forming an Examinations Group to consider future examination requirements for the NPPL. Will people opt for the JAR/FCL exams and their 100 hours of CPL ground theory time credit, or would they prefer a simpler exam - either as a single consolidated paper or as a simplified set of papers?
The upgrade accreditiation route to JAR/FCL PPL from NPPL will also be looked at - this will probably require theoretical and practical training as well as the JAR/FCL Skill test and JAR Class II medical, but the actual level of accreditation won't be known until the CAA has had a chance to assess the NPPL training syllabus.
So it looks as though multi-step flying training may be achievable at last:
Start with gliding.
Obtain a NPPL medical approval.
Obtain a NPPL with microlight rating.
Earn accreditation towards the NPPL with SEP rating
Obtain a NPPL with SEP rating
Earn accreditation towards the JAR/FCL PPL
Obtain a JAR Class II medical and pass the appropriate theoretical exams.
Pass the JAR/FCL PPL Skill Test
Upgrade to JAR/FCL PPL
Upgrade to include night qualification and IMC rating
...and then think about professional flying?