Hello, Kisa,
I can't answer the entire question, but I'll make a few observations.
2 Forms of Electronic Communication
Email:
Email makes communication much more efficient and provides a record for future reference. It can address many people at once, and is nearly instantaneous. It has led to dramatic increases in productivity and has allowed employees to work from remote locations, either for travelling or work-from-home. A wonderful development for most communication.
There are a few downsides. The absence of eye-to-eye contact prevents the visual communication that comes with posture, eye contact, grins, etc. Humans have become adept with using emotional communication. This does not occur with email, and information can be misinterpreted with out it. "I agree" in an email has a different meaning than "I agree" with eye crossed or head shaking no. Even slight motions signal a quite different answer.
A second downside to email is the "Reply All" option, which is often used by mistake. This is one of the fastest, most efficient, ways of creating havoc or laughter. A coworker responded to a notice about use of a conference room with "Bite me" to the writer, in jest. He hit "Reply All" by mistake, and it went to everyone, including the division president. Memorable, and HR got involved.
Video Conferences
Similar arguements can be made for video conferencing. This is often substituted for actual meetings, but some of the interpersonal communication is still missing. Good collaboration depends on working in the same space and having contact outside of formal meetings. Friendship and comaderie are important elements in teamwork. Video conferencing may be more efficient than travelling, but it infers a separation of people that can be detrimental to teamwork.
I don't have the time to answer the second question of comparing a multi-generational workplace. I would presume that the younger generation is developing a proficiency of using these new tools faster than the older generation. The use of acronyms and icons may becoming substitutes for subtle communication techniques. The younger generation is developing a skill that helps address these weaknesses.
Bob