Using several Flag fields and some new bar styles, it is possible to change the bar color.
To the best of my knowledge, you cannot set Text styles in that manner.

The values for the Status field are:

Complete = 0
On Schedule = 1
Late = 2
Future Task = 3

You will need four flag fields - one for each of the status possibilities.

For the custom formula try:
IIf([Status] = 0, Yes, No)

Change for each status in each one of the four flag fields.

For details on creating bar styles based upon Flag fields see FAQ 31 at:
http://project.mvps.org/faqs.htm