With Blockchain.info growing at about 1.5% per day? The rate of Bitcoin adoption is getting faster because of network effects. It is on an exponential adoption curve. Looks at Facebook, Evernote, Paypalor Dropbox usage for similarities. Imagine SD revenue with 3m Blockchain.info users which is realistic by slightly increasing current growth rates in 12-18 months.
SDice revenue is not guaranteed to rise with more Bitcoin users. With 3m Blockchain.info users bitcoin price in USD would surely be higher but because of the fixed number of bitcoins (I know total bitcoin supply still increasing but my general point still holds) then Bitcoin revenue might not increase. revenue (ignoring the luck element) can only increase if the amount of bitcoins gambled on SDice increases. So there may be 30x the number of Bitcoin users but on average they'd have 30x less Bitcoins so the average gambled on SDice per player may also reduce by 30x. If Bitcoin revenue/profit doesn't increase then the Bitcoin denominated share price should also not increase. Of course that share price will be worth a lot more in terms of USD.
Another thing to maybe think about is that part of SDice's popularity is the relative lack of alternatives for things to spend Bitcoins on. With a 3m userbase, Bitcoin will be far more attractive to other developers and entrepreneurs and I can imagine there will be many more alternative ways to spend your bitcoin thus more competition for SDice.
S.DICE is integrated into the wallet at blockchain.info like Coke is integrated into McDonalds