Since TIP started trading in 2003, its price has moved (mostly) opposite to rates. In mid 2007, the 10-year treasury yielded over 5%, and TIP sold for about 98. So if rates move up that much again, will TIP sell off to 98 again? I don't know. There does seem to be a fear-of-inflation premium built into the current price, since TIP is one of the few fixed investments that increases its payout as inflation rises. So I guess it seems to me that TIP is a play mostly on rates, with a lesser play on inflation.