It's not uncommon when a well-known, well-respected company is taken over by another of similar standing for there to be a process of 'orchestrated name-change' for one or both organisations. This usually follows a pattern, with some likely/possible variation of course, particularly if the acquired company's reputation has gone downhill. If the brand name or trading [business] name of the taken-over company stinks it'll not be used at all and re-branding happens overnight. If it's reputation is intact though the process is much as the following:

1. Both companies continue using their own individual names for a period of time, maybe even for the foreseeable future
2. The acquired company is 'tagged' as a subsidiary or branch or possession of the acquirer for a while, e.g. 'Navteq, a Nokia Company', while the parent remains 'Nokia'.
3. The association is tightened further, e.g. 'Navteq, a Trademark of Nokia' as has now happened.
4. Once that's sunk into the public psyche, it may become 'Navteq/Nokia' or 'Nokia/Navteq' or whatever, but maybe we could eventually see 'Nokia' the hardware manufacturer and 'Nokia Maps' as two separate entities with common ownership. Time will tell.

The speed of the process is usually in direct proportion to the height of the acquiree's reputation. The should be no rush to squander the goodwill associated with a highly regarded brand or business name of course.