Hillary unquestionably met or exceeded expectations tonight, and she'll get a deserved boost in the media and fundraising as a result. (According to the Clinton campaign, they'd already raised $2.5 million between the time the networks called the state and 11:30 pm.) This probably makes her a favorite to win Indiana (I thought she was a slight favorite even before tonight)--and, therefore, makes it pretty likely that she'll be in the race until the voting ends in early June.
But, having said all that, she only marginally improved her chances of winning the nomination, and they weren't high to begin with. She barely dented Obama's pledged delegate lead (she probably made up about 15-20 of his 165-delegate margin), and there are few indications that the superdelegates are prepared to overturn it. (Obviously, stay tuned over the next few days to see what the supers do.) That's particularly so if Hillary can't pass Obama in the popular vote, and she probably didn't make up enough ground tonight to have a shot.
The bottom line is that Hillary needs an Obama meltdown to have a real path to the nomination. After all the uproar about Jeremiah Wright and bittergate, that didn't come close to happening tonight. What did happen was that all the people who think the extended nomination fight is killing the party got a lot more depressed.