By playing two (or later even more) tables, you can fight the problem that arises when you get bored because you should play only 20% of your starting hands. Boredom might lead you to playing more hands than recommended, and thus makes you loose money. Playing multiple tables gives you more action and you will play less hands, namely the stronger ones.
Multitabling can be problematic, though, because you may not be able to use all the information from the hand - you may overlook details that can be important for your decision. Professional online players can play up to 8 tables simultaneously. They have trained their ability to grasp all the relevant information about a hand in a split second. But even these players mostly do not make the maximum per-table profit when they play multiple tables.
But you should choose the poker room where you want to multi-table wisely - not all have a software that allows you to arrange the tables in a perfect way so you can watch several tables at the same time. From this point of view, we recommed these rooms - with their software, you can arrange up to 16 tables by tiling them on your scree, with just one click!
Full Tilt Poker (download here), use bonus code COACH100 when signing up to get one of the highest deposit bonusses out there - $600 up to 100% on your first deposit!
Party Poker (download here), use bonus code PKR100 when signing up to get one of the highest deposit bonusses out there - $500 up to 100% on your first deposit!
Bet365 Poker (download here), use this link to sign up to get one of the highest deposit bonusses out there - $100 up to 100% on your first deposit!