W_i_t_n_a, I just checked their web site, and it does indicate "Full folders and multiple mail file support." This is very encouraging. From their web site, it appears that they also support "Push" (from MAPI clients only), and they do offer to sync wirelessly. These are promising starts.
If these features indeed work as advertised, then all I would need is a copy-into, to allow me to quickly take an email and convert it into an action or a calendar entry. Armed with this capability, the bar of processing email on a mobile device would be raised significantly.
One of the attractive features of the Blackberry has always been its nearly instant and seamless push of email & calendar. For Palm users, iAnywhere does that very well, too. I will add the Cadenza product to my "to review" list and have another look. It's been a while since I reviewed it. Thanks.
PS. It is encouraging to see your response. I'm going to ask some of the device & software vendors that I work with to respond, too. I want to see if we can help them see the value of GTD on a mobile device. I hope they respond.