All what I can say is that, for now Bitcoin is not outdated by any other 'cryptocurrency'. But in years to come, if no other crypto stands up to beat bitcoin in the game then it can still stand. Modern technology is always increasing; if another coin emerges to give what bitcoin didn't give, don't be surprised that this our favorite coin will be outdated. Or else if it is constantly update to match new modern technology.
The more accurate question would be "will Bitcoin be out numbered by other currency"? Based on the market history on trading anything can happened to any ALT coin project in the market, it may goes up and it may goes down depending on the volume of trust or confidence of investor on such project, the market react on any movement by other crypto currency on the market, the fundamentals of Bitcoin now is more stable, investor are gaining and growing support on Bitcoin project does reflect the stable prices on the trading market, the global acceptance on crypto currency market is growing each day and it also increase investor the demands, and this is just few indicator that Bitcoin will stay on top of crypto currency market.
to me i think that it can be possible but not so easy, in fact bitcoin is the fundamental currency of all the crypto world therefore it will survives for a long long time and will remain as number one, i do not think that any other currency can so easy bypass bitcoin and can left bitcoin behind.