Well, I should agree with the previous speaker - Zaurus SL is much more superior to pocket pc. It supports all the general stuff like calendar, email, addr book, word, excel and powerpoint - although all of them are not microsoft versions. They work with microsoft peers just fine (since it was designed with the existing state of things in mind, which is good). Pocket streets - i think you could do it with mapquest.com this time. GPS - nothing heard of it, but there is already a mobile internet with verizon that they offer. I think GPS is on its way. Wireles LAN - this is how I am writing you this message. :-))) There is already a huge community behid Z and it is growing each day. It has more than 70 open-source projects already on sourceforge.net and commercial software is available also (like Jabber thekompany.com, which is icq+msn+aim+yim client which is cool). Generally, even the interface is better (qutopia) and my pocketpc addicted peers had to acknowledge - it looks and works better. :-))) Multimedia player is also there. Plays mp3 and mpeg1, but not divx... So, far... but it is coming.Not to mention things - if you will start mentally to outgrow your pocket pc - you have nowhere to go, with Zaurus SL - there is a whole Linux world behind!
P.S.: Did I mention that cool keyboard which I work with my company's big irons on the go via the terminal shell? But it is pretty small for such a large messages like this though... uff...
My advice would be - buy certainly. It is very easy to use, syncs with MS stuff and fully expandable.
Check www.myzaurus.com for more info.
Hope this helps.