2 mins with Firefox 1.5

These few days, everyone been so excited about the new release of firefox 1.5 version. Everywhere you go, they're talking about it, posting about it.
So I thought what the heck and tried testing it out though I'm very satisfy with my current version 1.0.7.
The result was not at all satisfactory. After installation of the new version, it broke most of my extensions from version 1.0.7.

My four most favorite extensions : ScreenGrab, JustBlogIt, delicious and most widely used LoremIpsum been disabled due to incompatibility with the new firefox 1.5.
I was like, damn that's no good!, and within 2 min of testing, I reinstalled my old version 1.0.7.

Gladly enough all my extensions back to normal.

Ok, so remind me again what's so different/good about this new 1.5 version from 1.0.7??
People talk about how fast the new one is but for me it totally slow down my net. Plus it take hell lotta time to start up.
I think I'll just stick to version 1.0.7 cos' I'm so use to it. I won't try switch again until and unless someone show/tell me with the proper evident that the version 1.5 is superior over 1.0.7.