Biotech would be that sort of thing, although enhanced musculature would be primarily a street upgrade. For climbing, I'd suggest tiny hairs like spiders and geckos use. For computing, I'd actually say that it should be "you can't access the Net without an PNI". PNI is for Personal Network Interface, a name I'm suggesting for the retinal-HUD thing. That would provide another distinction between the upper and lower classes - the uppers can get a PNI easily, and indeed have them even as young children, but the lowers can't, which just helps to keep them lower-class.

I like your ideas for the Matrix.

Corporate rule... I'd say actually that we still have a "traditional" government, it's just [i]completely under the control of the corporations[/i]. That way, you still get politicians running for elections and so on, and it still looks good in the international community, but in reality the big companies pick and choose who gets in (and often put up their own candidates).

As for space travel, that could be interesting, but I think again it would depend on where they're from. Upper-class people can probably get into space whenever they like, but the lower class have to either be sent there by their upper-class employers or go on illegal black-market flights that are unreliable, incredibly expensive and often try to ransom the passengers. That could make a good plot hook, actually - character X has to rescue one of their relatives.