Not exactly. microB is based on gecko engine, and - possibly - older builds of Firefox, with some patches by Nokians. Thats why *some* addonds may be - with much work - made to work with microB, like addblock was.

Ho ever, it's *not* firefox, and it's not compatible with firefox builds. Also, it's *not* Open source (microB), so we can't upgrade it.

If anyone feels adventurous, got infinite ammount of free time, and is sure she/he can handle everything, that one may try creating Open Source Micro Browser for N900, based on new firefox source code