Quick answer is no. The main icons within the HTC front-page theme are clickable with a fingertip, but the onscreen keyboard is far too small. I have brilliantly managed to lose my stylus (awaiting first delivery of spares!) and find even with good nails, selecting SMS, navigating menus and the like is tricky. If I've cut my nails, especially index, middle finger and thumb, it's hard. If you have hands that didn't do dishes, (UK joke) then you will need the stylus.
This is one area the apple iphone has scored in, a much larger onscreen keyboard and icons.
The HTC devices can obviously have a bigger onscreen keyboard downloaded from software vendors worldwide, but this helps sms and text entry, it doesn't help with menu navigation much.
Upshot: people with medium sized hands and nice fingernails can use the unit without the stylus, everyone else will get frustrated. If you use a lot of texts and data entry, buying a third party onscreen keyboard program may save your day without spending the whopping money of a 18 month iphone contract.
Regards
Ivan