With everyone on Twitter nowadays, from laypersons to celebrities, to hackers and politicians, it’s not a surprise as to why more companies are investing in the microblogging site.  In December 2010, Twitter received a $200 million funding from Kleiner Perkins Caufield & Byers, Spark Capital, Benchmark Capital and Union Square Ventures and with that their value was estimated at $3.7 billion.

And now, Twitter is close to completing an $800 million funding round from DST Global, which has also invested in Facebook, Zynga and Groupon.  Other investors have not yet been made public.  The funding is said to be a two-staged deal wherein $400 million will go to the company itself, used for its improvement and expansion, while the other $400 million will be set aside for cashing out employees and existing investors.  This is for basic funding purposes and also for monetizing privately held stocks.

The deal is reported to happen in the next two weeks and will increase Twitter’s value to $8 billion, doubling its value from earlier this year.

Twitter’s hoping to  build revenues around advertising and other marketing streams, with promotional and paid tweets for starters.  The microblog has had quite a time determining the best way to incorporate advertising into its network, though a recent comment by CEO Dick Costello indicates Twitter’s plans around e-commerce and hyper-local markets.

“There’s a commerce opportunity there for us to take advantage of if we want,” Costolo said during a keynote interview at Fortune BrainstormTech in Aspen. “How can we remove friction from the process?”

There’s few details on how Twitter actually plans on doing this, though its string of acquisitions in the past year have greatly extended its presence in the mobile arena.  With competitors like Facebook and Google incorporating more localized offerings around discounts and actions, Twitter would do well to find its place in this trend as well.