The 9.62% rate is for the six-month period, after that it's probably falling to 6+%, which is still better than anything else you'll find out there in terms of inflation-proofing cash. But it requires a five-year commitment, with a minimum of 12 months before you can pull your money out, but you'll lose the final three months of interest if you pull your money before five years. $10k per SSN with no household limit.

I believe today (28th) is last day to pull the trigger on this.

I Bonds make sense if you have a bunch of cash like an emergency day fund sitting in a savings account. In theory at these rates you can inflation-proof more than 10k by putting only 10k in. I think if you had a 20-30k emergency fund, I Bonds make a lot of sense. But if you have 20-30k sitting around for project work in the coming year (where you need access to the cash), it isn't really a good fit.