Technology Acceptance Model

I just found a paper online (PDF) that I think can inform the adoption of portfolios. The authors discuss the Technology Acceptance Model, that relates perceived usefulness and perceived ease of use with a person's attitude toward using, behavioral intention to use, and actual use of a system. There are other factors, as well, including self-efficacy and cognitive absorption, as discussed in this excerpt:

Agarwal and Karahanna (2000) further developed the concept of self-efficacy to analyze the relationship between self-efficacy and perceived usefulness and perceived ease of use. Adding the cognitive absorption construct, they further modified the TAM model from Agarwal’s original study (1998). The three aspects of cognitive absorption research are the personality trait dimension of absorption, the state of flow, and the notion of cognitive engagement. The study was done using the World Wide Web and university students. PLS was used to establish the nomological validity of cognitive absorption. The hypotheses that cognitive absorption is a significant predictor of perceived usefulness and perceived ease of use were supported by the results. They also found that playfulness and personal innovativeness have strong significant effects on cognitive absorption. (p.4)

I thought the point of playfulness, absorption, state of flow and cognitive engagement were key constructs that could also apply to the development of e-Portfolios.