This is a quick modification that looks up the now value only if the transformedValue is nil when it's about to be returned. In our app, Couple, we noticed a slowdown from the repetitive lookup of the now value at every relative date transform which happens a lot when you scroll through our timeline of messages.
Actually, hold on with the merge, there are a few issues with the code and it pulled in an extra commit I didn't intend to add.
performance improvement for default now return
Ok, it's ready to go now - the commit should be clean.
Thanks very much!