As a complement to this post, I am having the very same bad experience with hosting-pp. My site has been unreachable since Jan 1st 2007 (already 5 days) and after raising a trouble ticket to Tech Support I got a similar (and ridiculous) answer: because of a planned server upgrade to increase the memory and provide a better speed.

No warnings were sent to me about a possible downtime and when I explicitely requested a date when the service is supposed to be restablished, I got a vague answer like they will contact me as soon as it is done.
I raised a second trouble ticked addressed to customer service asking again explicitely about a date when the problem will be solved and after 36 hours, I am still waiting for an answer.

In short:

- Planned upgrade without warning the customers? Very professional...
- Downtime of many days without providing any sound explanation? They are definitely the providers NOT to choose.

The 99.999% uptime announced on their homepage is really an illusion.

And retaking jwbworks words:

Please, learn from our mistake!