Are there any gotchas with using two Apple IDs for one user in the App Store? To date I have had an Apple ID tied to my personal email address. It uses my personal paypal account for the purchases, and currently it has a credit balance thanks to some Christmas iTunes gift cards.

With the App Store recently being released, I'd like to buy an OS X app for business purposes. I don't want to use the credit balance on my personal Apple ID account, so I was thinking about creating a new Apple ID just for when I buy apps that I use for business. This way I could have the business Apple ID tied to my business paypal account.

However, I'm concerned that there might be some gotchas with using two different Apple IDs on the same MacBook by the same user. Before I just try this blindly, does anyone have any experience or know of any gotchas?
There are a couple of gotchas I'm aware of.


If you buy apps on both iTunes accounts, they all get listed together when updates become available, not just the ones on the account you're currently signed into.  So if you click 'download all free updates' iTunes will only download the updates for the account which is signed in.  This can be confusing because you've told it to download all free updates and it doesn't tell you why it hasn't downloaded the others. 
If you have an Apple TV and you want to use Home Sharing, then you can only share the content for one account at a time.