Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of SINA Corp (NASDAQ:SINA) rose more than 10% early Thursday, then settled to close up around 8.5% following reports an IPO of its Weibo microblogging site could come soon.

So what: Specifically, a PrivCo report cites sources familiar with the situation saying a Weibo IPO might happen as early as June. In addition -- based on its own analysis and considering Twitter's IPO and Facebook's acquisition of WhatsApp -- PrivCo claims Weibo could command a valuation of up to $8 billion.

Now what: That means the offering could raise at least $1 billion for Weibo's owners, which, as of last April, include 18% stakeholder and Chinese e-commerce specialist Alibaba. But at the time, SINA also granted Alibaba an option to increase its ownership to 30% -- something that would almost certainly happen before an IPO.

This also mostly meshes with a Wall Street Journal report last week, that suggested SINA was planning to raise around $500 million by listing Weibo sometime in the second quarter. 

As I also noted last week, we should also keep in mind Weibo has faced political uncertainties from the Chinese government, which, in the past, launched an "antirumor campaign" aimed at stemming the influence of such mediums. In the end, the market may very well be willing to look past this risk, but I'm still not personally compelled enough by Weibo to dive into shares of SINA today.