From an investor perspective, what the heck are Telkom gonna do with all the money they are going to get from selling their stake in Vodacom (or most of it anyway) to Vodafone, shareholders on the JSE and/or empowerment partner? And added to this, all the money they will make from selling assets to MTN? For arguments sake lets assume it will be about R70bn to R80bn ($11bn to $13bn).
Telkom Media will not be able to absorb all that cash in a short time. I dont think there is a big enough company in Africa, never mind South Africa, for any kind of takeover/merger of that size, except maybe a few mining companies (Harmony, Goldfields, ImpalaPlatinum, maybe

), a few investment/holding companies, or banks. More likely, one of the smaller mobile companies or lots of smaller acquisitions of a few R bn each. I mean, the Business Connexion takeover was only R2.4bn. Alternatively they will have to buy shares back from shareholders - probably govt, but even that wont be enough to get rid of all that cash.
If they dont, they make themselves prime targets for takeover - there are many companies / investors that would love to get their hands on $8bn to $10bn in cash through a takeover, and then sell the company (probably in bits and pieces) once they have milked it and spend the cash elsewhere.
That is partly why from a investor perspective, I dont think the MTN-Telkom deal will go through. At least not as is speculated in the business media in SA.