One of the important things to consider with 126.96.36.199 is support. I think Extended Support ends Nov 2013 and without support I’m sure your business will want to upgrade.
You could wait for 12.2, but I wouldn’t want to implement a product with a brand new application server, until a few bugs settle out. 12.2 will use Weblogics.
The 12.1 upgrade is a functional upgrade and the 12.2 is a tech stack upgrade, probably with 188.8.131.52 for the DB. The big deal is WLS and the administration of possibly much more complicated configurations.
At OOW, a development manager at Oracle said that all the platforms, Peoplesoft, JDEdwards all have to run on WLS before they can attempt a “fusion” of the products. This seems a bit obvious, but illustrates the fact that Oracle will be really pushing us hard to 12.2.
If you really want to take on the complexity of educating your users in a completely new way of accounting and trying to resolve new undocumented AS issues at the same time by doing a 12.2 upgrade, good luck.
I think the more sensible approach would be to upgrade to 12.1.3 and then 2 years later upgrade to 12.2. Since, it’s primarily a tech stack upgrade with bug fixes, the users should not need to be retrained.