Using the iPhone as a BlackBerry

It's been a month since I gave up my BlackBerry and turned to my iPhone as a replacement for my work email and calendar. I'm mostly happy with it. Here are my thoughts:

<> It's really nice to have a single device for all of my stuff. The strength of this benefit is even greater than I expected.
<> The iPhone keyboard is nowhere near as good as the BlackBerry's. Not even close. With the BlackBerry, I could bang out emails with almost as much ease as I could on my computer. I never had to postpone writing a long email on the road. With the iPhone, I only have patience for tapping out truncated, "this will have to do for now" messages. This is a big step backward.
<> The iPhone's offline support for Exchange is very weak. When I'm out of cell range (i.e. on the subway) and I try to delete messages from my Exchange account, or write new messages and try to send them, I get connectivity errors. This is pretty basic stuff- the iPhone should cache those requests and batch them when the device gets a connection, not throw up errors.
<> I like the iPhone's Exchange calendar support. It's more elegant than the BlackBerry's- but you can't create appointments and invite people to them from the iPhone, which is a major limitation.
<> There's no support for multiple e-mail signatures. I have three email accounts on the device, and I'd like to have a different signature for each- particularly for my work account. The iPhone only supports a single signature.
<> There's no support for setting an out-of-office message on the iPhone. There is on the BlackBerry.
<> Lack of copy and paste support is a real bummer.
<> Lack of support for Exchange tasks and notes stinks too.

So there are a few positives, and a lot of negatives. Still, I wouldn't go back. The convenience of having one device for everything trumps all of the negatives, and I'm hopeful that most, if not all, of them will be addressed in upcoming software updates.