Expanding the character limit is on the list for a future release.
We had listened to our customers and scheduled the campaign level/negative KW functionality as a priority. It wasn't possible to combine the two feature requests in the same release for technical reasons.
I have notified the product team about losing the commas and they're looking into it.
Please do keep your feedback and suggestions coming - they are all read, noted and passed on.
I rarely make any changes to my MSN campaign. The amount of time it takes me to go through the three or four steps to change a keyword bid or change anything for that matter....it's not worth it to me. Mostly because our MSN ad spend and conversions is a tiny fraction of the whole...and I can put that time to a much better use in G.