You aren't looking at the specs very closely, NVidia is doing mobile pretty good. At least reasonably competitive with ATI. More so the video acceleration from NVidia is pretty good.
Well, they are second place. Out of two competitors
AMD chips weren't low power enough and I don't think they had features like Optimus. Plus their OpenCL drivers were behind NVidia's by a long way.
I don't know of any OpenCL uses in apps, which isn't to say there aren't any, but rather that that may not be a dealbreaker. Also, I recall reading elsewhere ATI/AMD have surpassed NVidia in OpenCL, certainly as far a 200-300 series cards. 400 series NVidia cards won't be in MacBooks... er... anytime soon. Unfortunately TDP and size weren't really considered during the 400series design phase(?). For any given TDP category, ATI generally offers more graphics power.
Apple, supposedly, doesn't use Optimus, though they may be using the same hardware features and calling it something else.
NVidia's mobile strategy is to ship their products from 4 years ago, on a modern process, for laptops. ATI's strategy is to pair down their current offerings to fit laptop power/thermal envelopes.
according to notebookcheck
The Nvidia GeForce GT 330M is the successor of the GT 230M and technically a faster clocked GT 240M (but it should still maintain the power envelope of the GT 230M as the naming suggests). Therefore, the GT330M is a mid-range laptop graphics card that offers DirectX 10.1 effects.
The performance of the GT 330M is similar to the GeForce GT 240M and therefore located in the range of the Mobility Radeon HD 4650. The card supports DirectX 10.1 and all the features of the GT 230M / 240M (as it is based on the same GT216 core). The modern ATI Radeon HD 5650 offers DirectX 11 effects and performs better.
Modern and demanding DirectX 10 and 11 games (like Crysis or Risen) can only be played fluently with medium detail settings and resolution settings. Less demanding games like Sims 3 run in high details and resolutions. See the gaming list below for detailed benchmarks.
The 48 shader cores of the GT216 are based on the desktop GTX 200 architecture and are therefore a bit improved compared to the 48 cores of the GeForce 9700M GTX. According to Nvidia, the micro architecture was improved regarding battery runtime and performance. The stream processors / shaders are 1-dimensional (1D) and can therefore not directly compared to the 5D shaders of current AMD / ATI cards like the Mobility Radeon HD 5650.
To use the calculation performance of the GeForce GT 330M for other applications, the card supports CUDA, OpenCL, and Direct Compute. For example encoding videos using the stream processors is considerably faster than using a fast CPU.
The GT330M supports the hardware decoding of HD videos using the integrated PureVideo HD engine. The integrated VP4 video processor is able to fully decode H.264, VC-1, MPEG-2, and MPEG-4 ASP (e.g., DivX, xVID). Hardware decoding of MPEG-1 encoded videos is not supported, but this can be handled by every CPU without high load. In conjunction with an Core i5-520M, the GT 330M decoded H.264 with 1-6%, VC1 in 5-10%, and WMV with 3-9% CPU load (1080p over HDMI on a Sony Vaio Z11).
As with the GT 230M, the performance depends on the used graphics memory. With slow DDR2, the card can be up to 20% slower than with faster memory. Usually the GT 330M is paired with cheap and relatively fast DDR3 memory. GDDR3 would be a bit faster. GDDR5 is not supported according to Nvidia.
A low power version of the GT 330M is also available for laptop manufacturers featuring a minimal slower clock rate and less power consumption (Codename N11P-LP).
The AMD ATI Mobility Radeon HD 5650 is a middle class DirectX 11 graphics card for laptops. Its based on the Madison (LE, LP or Pro) chip and is produced in 40nm. Like its predecessor, the Mobility Radeon 4650, the HD 5650 features a 128 Bit memory bus for dedicated DDR3 and GDDR3 memory chips. GDDR5 is rumored to be not supported on the HD 5650 (only in the higher clocked versions like the 5700 series).
In our benchmarks with the HD 5650, the GPU is performing on a level with the previous Mobility Radeon HD 4670 or the Nvidia GeForce GTS 250M (with DDR3 graphics memory). This means the performance is sufficient for high details in nearly all DirectX 10 games (only Crysis and GTA4 are not fluently playable in high details - see gaming list below). Upcoming and current DirectX 11 games (like DIRT2) may not run in full detail settings. That means some of the new DirectX 11 features (Tesselation e.g.) may not run fluently on this gaming graphics adapter. Currently the HD 5650 is a good gaming pick for well priced laptops with a 15 inch screen and a resolution of about 1366x768.
The Mobility HD 5650 supports Avivo HD to accelerate HD videos using the graphics card. The improved UVD2 processor in the DirectX11 models of the Radeon HD 5000 series is able to decode up to two streams in parallel (if the card offers enough memory bandwidth). It is not clear if the HD 5650 using (G)DDR3 offers enough bandwidth for this task.
Another novelty of the HD 5650 is the possibility to transport HD Audio formats (8-channel Dolby True HD, DTS Master) over the HDMI port.
Thanks to Eyevision, up to 6 monitors can be used with the HD 5650 in 3D and 2D applications. In most laptops this number will be limited to max. 3 (2 external and the internal display).
The power consumption should be (due to the modern 40nm process in 2009) relatively low and according to rumors about 10-15 Watt.