I think every partner should look at it as an opportunity to have a leading switching and routing portfolio added to your company and thus giving you a better chance to win. I can't imagine why you wouldn't want to offer the whole portfolio if its at your disposal. This is what the merger is about, bringing awesome end to end solutions to the customers, not cherry picking and piece mealing from multiple vendors. It's hard enough to get people away from Cisco to another single vendor, it's even harder with a multi vendor solution. In the end it should be easier for you as you have one company to work with vs multiple from a partner/vendor perspective.
HP is the defacto #2 switching vendor out there. HP competes with Cisco everyday (and thats our goal), we're not competing head to head with the Avaya, Brocade or Juniper vendors very much. We are 9 times out of 10 on the shortlist for RFPs, those other vendors can't say that, only Cisco and HP (IMHO). Aruba is the #1 WLAN technology, but behind Cisco in market share. Aruba is the only one that competes with Cisco in WLAN like this, so I see the merger as a great thing for us all.
To ease your concern in the short term until we find out what will really happen I can only point you to this statement. I believe this will become the practice once the companies merge as there's not enough HP Networking partners out there.
http://www.arubanetworks.com/aruba-and-hp/?source=homepage
I'm confident this is what happens, HP needs more partners and better partners. Especially ones with WLAN knowledge, we lack that severly today. Good WLAN partners are very very hard to find.
As for competing against another HP partner I don't think you'll run into that much as you think. If you do then its your responsibility as a value-add to offer services above and beyond the other partner to make the customer want to pick you. As for margins that is also your responsibility to register the deal with HP to lock in higher discounts for your organization that no one else can get. I'm not sure if Aruba does this, but this is a practice that HP does to show commitment to the partner that is out there hunting for the deal. This stops freebies and sniping of customers from other partners!
Keep your head up everyone.!!
These are my opinions