seriously using hotmail for business (or any) use?
Nothing personal, but anyone who hasn't realised how dated, featureless and substandard a service Hotmail is in comparison with other providers (who actually dare to invest and move their services forward) does kind of bring this on themselves. Given it's reputation as the underworld for lowlife spammers, I would instantly distrust anyone using it for a business related purpose - in fact it would prejudice my opinion of their professionalism. For personal use, you cannot fail to be aware of its shortcomings and therefore you would also be mad to choose to use it.
I use about 3 different addresses for hotmail for the reasons given by Adam above, and admittedly the lesser used ones have less spam, but its the very poor filtering that is the problem. With any email provider, once your address has been "acquired" by spammers then the game is up - it will never be spam free again. However, the spam that makes it past my main Yahoo address amounts to about 1 a month vs 20-25 on Hotmail. Conversely, occasionally email from a domain I haven't received from before is precautionarily filtered by Yahoo, but not to the extent that I cannot leave it for up to 2 weeks between checking it.
Most people I know only continued to use Hotmail as their main account because they used MSN Messenger, but now you don't have to have a Hotmail/MSN address for that, even those numbers fall further and further.