As of 14.7.10 morning in India (13th night in US), sp1 BETA IS OFFERED THROUGH WINDOWS UPDATE. Check for updates and it offers SP1 BETA.
acyuta, you must have run the WUSignUpTool mentioned a couple posts up, right? MS is not pushing SP1 out in WU unless you make that change.
Could be. I installed that WUsignup tool yesterday evening hoping to download the SP1. Nothing happened. However, today morning, it was in the windows update box. If windows is up to date with previous updates, the SP1 is perhaps 45-50MB (for 64 bit enterprise). The visible difference in Windows Update SP1 is no watermark (SP1...) on desktop after install.