There has been a lot of discussion of late around Apple's reported push towards flatter designs. Others, such as Microsoft are already said to be bucking this trend with it's Window's Phone metro design, along with Facebook and it's new 'f' icon design.
Designs with more 3-D and life-like appeal have been popular for some time. Such designs were highly popularized by Apple for their skeuomorphic qualities. This approach added more realism, richness, and familiarity to design elements and helped bridge the gap between the physical and virtual worlds for users.
The trend and chatter now seems to be revolving around the antiquity of this approach and suggests that it is potentially not meeting the needs of today's modern users. For instance, younger users might not be familiar with some of the real-world metaphors commonly used such as a rolodex, and highly stylized, multi-dimensional elements might be overly complex for today's mobile needs.
Either way, the push for a flatter design direction is an indication of evolving esthetics, needs, and demands by users. Flat designs would introduce a more streamlined and contemporary feel; it would help reduce elements to their core elements thereby eliminating any unnecessary visual detail; and it could aid in making downloads faster especially on mobile platforms.
While a flat design might suggest basic and unimaginative, flatter doesn't have to mean less visually appealing. Interfaces can still be clean, colorful, and have some dimensionality and layers yet still appear elegant and lightweight.
Perhaps, it is time to move the design needle forward to simple and modern yet effective designs which are a reflection of our busy lives and need for quick and easy access.