I've found that even some of the BIG IPO's go up and STAY up in price, and others go up and then drop. I've also found that some of these bigger IPO's also end up being 'slow bleeders'... and will end up dropping 10 cents here, 50 cents there, etc. until they settle at whatever their 'bottom' price is before they start a slow climb again as their release date nears.
Everyone has their own style of trading... and you have to decide if a stock is worth keeping & tying up the $$ (if you have the $$ to spare) or if you sell it off after making some $$ on it and use your cash elsewhere. If you hold it, you have to be willing to ride out the roller coaster in price sometimes. If you have the cash to tie up and you don't mind the swings then you can hold on to the bigger IPO movies..
Good luck!