Recently, I had ocassion to program a 16F870 using the PICkit 2 and programming failed. This lead to an exercise to find out why. Devices made in 2001 and 2011 were tested with the conclusion that early devices were not defective vs. newely purchased ones. A very early version of the PICSTART Plus and a recent version did not work. I must have done all the 16F870 work in 2001 and 2002 using the original ICD (not my PICSTART Plus) as no programming problems were experienced. The emphasis was on in-circuit debugging at the time (a new development), so it is not surprising that I did not use my PICSTART Plus and discover this problem then. The ICD 2 works.
The conclusion is:
If you want to use a PICkit 2 to do the device programming called for in "Microcontrol'n Apps" or "Time'n And Count'n", I urge you to use the F882 in lieu of the F870. Instructions on how to go about this are also under the Updates link on this web site. A further incentive is the F870 is being phased out.