Posted: 14/03/2012 at 12:15
As meiow and jeffd say, it's a variegated umbrella plant (Schefflera arboricola). These are prone to scale insects, which cause the plants to be covered in a sticky film, whilst weakening them. Schefflera can also be attacked as you say by thrips, and mealybugs. Mealybugs can also cause leaf stickiness but you probably would have spotted them as you'd see the pale 'fluff'. It can be hard to spot scale insects as they can hide in crevices in the plants. After the danger of frost has passed, you can put your plant outside for the summer, that will help you to deal with these conservatory type pests. But have a look at the controls set out in the links above.
Shore flies / fungus gnats are annoying and can leave faecal spots on your plants, but they won't cause harm. Try not to water too much, to reduce the wet conditions they favour.