"I think it doesn't matter what I think. The market will decide what it's worth," Kevin Landis, whose Firsthand Technology Value Fund (SVVC) counts Twitter as 11 percent of its holdings. "But if you want to put a ceiling on how much it could possibly be worth, the current value of Facebook is probably a good ceiling, given that Facebook is further along in their progress.
"And if you want to put a floor, I'd say the private market trades, before it heated up, so, from six months ago, those numbers say it's $9 billion. So, it's a wide range, but those are your boundaries."
Facebook's market capitalization stood at $107.9 billion as of midday.
On CNBC's "Fast Money," Landis said that Twitter's value estimate of $600 million to nearly $1 billion from eMarketer was just a guideline."Chances are that eMarketer number is wrong. It's just a question of: How wrong is it?" he said. "It seems like it's in the right ballpark, though, and it seems to track the other things we're hearing, so it's a reasonable number. The problem with that number, though, it's the only number that's out there right now, so everyone's grabbing on to it like it's a really hard data point. It's an estimate."
Landis also said that Twitter would avoid one of the stumbling blocks with which Facebook shares met.
"When the Facebook balloon got punctured, everyone said, 'What's their mobile strategy?' I don't think we need to worry about the great debate: What's Twitter's desktop strategy? That's not going to happen," he said. "So, that's one problem that they don't have.
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"But don't worry. It's a crazy world out there. There'll be plenty of other issues that'll crop up if people are looking to poke holes in the story."
Trader disclosure: On Sept. 13, 2013, the following stocks and commodities mentioned or intended to be mentioned on CNBC's "Fast Money" were owned by the "Fast Money" traders: Stephen Weiss is long AAPL CALLS; Stephen Weiss is long BAC; Stephen Weiss is long C; Stephen Weiss is long FB; Stephen Weiss is long C; Stephen Weiss is long TBF; Stephen Weiss is long MOS; Pete Najarian is long AAPL; Pete Najarian is long C; Pete Najarian is long MS; Pete Najarian is long INTC; Pete Najarian is long BBRY; Pete Najarian is long SBUX; Pete Najarian is long FB; Joe Terranova is long VRTS; Joe Terranova is long MOS; Joe Terranova is long OXY; Joe Terranova is long APA; Joe Terranova is long MS; Joe Terranova is long GS; Joe Terranova is long SBUX; Joe Terranova is short XBI; Mark Fisher owns CVX; Mark Fisher owns HES; Mark Fisher owns MPC; Mark Fisher owns PSX; Mark Fisher owns VLO; Mark Fisher owns ABX; Mark Fisher owns EGO; Mark Fisher owns GDX.