Microsoft extended the deadline for Windows 7 beta downloading till February 10, but people could complete their download till 12th February. There will be no restriction on product key and if you will not have your product key, you will be able to do so even after 12th February.
According to Windows blog, the reason cited as:
Because enthusiasm continues to be so high for the Windows 7 Beta and we don’t want anyone to miss out we will keep the Beta downloads open through February 10th. Customers who have started but not completed the download process will be able to do so through February 12th.
Presently, Windows 7 beta 32 bit version available in five languages including Arabic, English, German, Hindi and Japanese. 64 bit version of Windows 7 beta is not available in Hindi language. You can download Windows 7 beta from here.