According to US The Loop survey, it may be possible that the Firmware of the future iPad and the one of iPhone won't be the same before autumn.
iPhone Firmware is actually 3.1.3, the iPad is announced to Firmware 3.2 and the 4th generation fo iPhone in June will be with 4.0.




This new Firmware 4.0 will bring many improvements but won't join iPad and iPhone in June.
A Firmware 4.1 would be more logical in autumn, same for iPhone and iPad, and it would permit to solve most of issues met on 4.0.