I type just as fast and accurate on my iPad than I can on a physical one. My Galaxy Nexus keyboard lags too much and does double letters, but I still can type about 10x faster than a stupid hardware keyboard on any phone! On my iPad, I have some shortcuts as my personal dictionary. In addition to stuff like "hwu" for "Hey what's up?" I also have "hahaha" for "hahaha" so I can use those words.
I use my iPad type multiple essays a week, write forum posts (I did an 800 and 1100 word one last week, mainly do them on The Verge), tweet, write emails, and take notes during class. As a high school student in AP Classes and taking college courses, I have adapted to 100% iPad (except printing off my school's printers). It took a little time to adapt, but I prefer it now way over any physical keyboard. Autocorrect saves my life lol.
Btw, I typed this comment on my phone.