Always a controversial area. Obviously government intervention (or, interference?) held back developments in telephony, so as not to harm their investment in the telegraph. Despite this, the former overtook the latter. When was the turning point? Surely, other factors also impinged on the telephone's development, such as people travelling more, migration to urban areas, increase in commerce? Why was the Post Office so negative about the telephone? Was the system so perfect (with errand boys, telegrams, and twelve postal deliveries daily) that a telephone was superfluous? Did they really need to invent a need for it?
Another controversial area. These categories are not immutable and fixed in concrete. They change over time so we mustn't look at, say, gender roles in the Fin de Siècle and assume these are the same gender roles that we know in the year 2010. What could be examined is how telecommunications technologies mediated class/gender relations of the time and whether use* of these technologies reinforced/weakened those relations. For example, how did domestic practices change when a telephone appeared in the hallway? Who answered it? What was the involvement of servants? A gentleman would never think of paying a "morning visit" to a single young woman (and certainly without her mother/chaperone being present). But what was society's reaction later when he could telephone her from the comfort of his own home?
How is the telephone represented in visual art, dramas, novels? How soon after its invention did the telephone start to appear in cultural artefacts? How soon is it before we can talk about the existence of a "telephone culture"?
The telephone in business and the workplace. Again, slighted related to class/gender in the sense of workplace relationships in connection with the telephone [boss/employee]. Particularly interesting is the introduction of the telephone in the City. An ultra conservative domain of the male, upper classes, the City did not welcome the telephone with open arms. Their business dealings were based on personal contacts, networks, gentlemen's agreements and word of mouth (see Kynaston's magisterial The City of London). That's how it had always been done and they saw no reason to change in a hurry.
Developments also occurred in general office work (more office automation - typewriters, construction of large office blocks in city centres, office work becoming more suitable for women - feminisation of office work). Telecommunications in industry/commerce, however, is too big a topic; it deserves a dissertation all of its own.
* Here I nearly fell into the trap of saying "whether these technologies reinforced ..." as if they had free agency. The discussion should revolve around "technologies-in-use" and what people do with them.