It would be one thing if they blocked you changing your default search... which they do not do. They are blocking a program from changing your default search. And who knows which one, it may not be any competition whatsoever...
Boy I like that feature. Frined wanted me to download yahoo messenger and it installed yahoo toolbar as well. I mouthed the whole time I uninstalled it and reinstalled Google. Next he says, download MSN messenger and I declined. Told him I did not want to waste my time.
Go for Trillian instead, you get all those and I'm sure it doesn't install any toolbars (it didn't for me anyways).