LGPL requires that the end user be able to replace the LGPL-licensed shared library, or it turns into GPL. The problem is, end users have no access to replace shared libraries in embedded or even mobile devices, so LGPL ==GPL there.
Of course this only matters to closed source software.
As an example of the above restriction, for closed source Mono requires a paid commercial license in embedded or mobile, because its runtime is LGPL. That is why I wouldn't touch it with a ten foot pole :-)
Given the raising importance of embedded and mobile, one might as well assume that LGPL is GPL. Nothing inherently wrong with that, but it does mean LGPL software is less commercially adopted.