The tip thing is just a rumor.
Well...it's a pretty strong rumor. Disney asked their union to approve removal of the gratuity from DDP and the union (most of whom are not servers) agreed in return for other tradeoffs.
I wouldn't worry about it until the full details come out.
Good advice. Usually, the DDP details for the next year are announced in August, so we should know for sure in a few weeks.
I believe that the DDP will still be a good deal even if tips were to be removed.
Whether DDP is a good deal or not depends on several things. One is your family composition -- if you have four kids under 10, it's probably a great plan for your family; if you have 10 y/o twins (@ $38.99 each) and both eat like birds, it may be an awful plan for you.
Another factor is your normal (or preferred) dining pattern at WDW. If you never eat TS meals, and don't want to, you'd be silly to get DDP. If you always eat TS meals and like to do character meals, DDP may be great for you.
Another important consideration to me is the length of the trip. We usually go for either 4 or 5 days. We like DDP for that short duration, but I don't think I'd get it for much longer than that. I'd just get tired of the standardized menus after 5 days or so.
And finally, "It depends on what the meaning of 'is' is." Some people compare the
sticker prices off the menus of the food they ordered to the
cost of DDP. I personally think that's a grossly inaccurate way to judge whether DDP saves you money. That's the way the Disney marketing kids get their bogus "40% savings!

"
DDP only saves you money, IMHO, if the cost of DDP is
less than what you would normally spend, following your normal dining habits, and using whatever other discounts you have available to you.
There are other reasons for getting DDP, besides whatever cost savings you may find -- but I think a lot of people buy DDP for the mirage of savings they get when they look at menu prices (which are inflated to begin with).