In this paper, we analyze a multiple-input multiple-output (MIMO) wireless system with dynamic radiation pattern diversity provided by composite right/left-handed (CRLH) leaky-wave antennas (LWA's). The CRLH-LWA is electronically reconfigurable with real time continuously direction-steerable radiation pattern and adjustable beamwidth. Analysis shows that these features match the clustered nature of indoor channels, and thus can provide high capacity gain by increasing received power. Furthermore, in MIMO systems the fully steerable direction provided by the CRLH-LWA is able to decorrelate the MIMO channel and improve the channel capacity. The results presented in this paper demonstrate that this is a highly promising approach for future high throughput reliable MIMO systems.