I have just managed to get the iPad from a family member and have come across a WordPress App.
It is simply a matter of adding the blog and then you can post. It does not have all the bells and whistles of the full version but it is very simple to use.
This is the first time I have typed any length of words on the keyboard and I like it. It is a small keyboard but with the iPad in a landscape mode it works very well. Touching the keyboard is very quick and the letters appear when you live your finger off the screen.
I will also try to upload a picture of the screen which I have just snapped.