Agostini holds almost all the records and will continue to do so forever because he raced two classes (350/500) at the same time, winning both championships from 1968 - 1972 and has a hand-full of other championships prior and post his domination. So thats 4 years of utter domination and 11 more championships, with a combination of 15 titles to his name. Nobody will ever beat his records, its actually impossible in todays world.
Marc's 10 in a row MATCHES Ago's record. However, to really put that record away and behind him, Marc will need to win one more. Mick Doohan's 12 race wins in the 97' season, is the only other record he'd need to break in terms of seasonal race wins. In terms of championships, Ago has 8 premiere class 500cc championships to his name. I don't see that record being matched or broken because the level of competition is a lot higher, technology is constantly in flux (may have a bogus bike for a few years) and the bikes are a lot faster. As a consequence, you simply burn out quicker and your days of being the top dog can end in a heart beat through a simple accident at an older age. Back in the day, the speeds were a lot slower, but the gear was almost nonexistent. So if you were smooth and capable of keeping it on two wheels, it was pretty easy to win. Even the all-mighty Ago retired from injury. It just happened to him 12 years after he started.
Its amazing to note, I'm pretty sure Loris Capirossi holds the record of longest time racing in the series. He raced for 21 years before retiring at the end of 2011. The current old-hat Valentino Rossi, has only been in the series for 18 years. There maybe someone else who's raced longer, but Capirossi most likely has better stats anyway.
As a reference, Marc's been only at it for 7 years, with 3 championships and maybe a 4th this year.