Since Android tablets are relatively new I would say Android phone and iPad. Android phones and their software have been around longer than their relatively new tablet brothers. On the other hand, the iPad has gone through a product refresh and it's obvious that there's a sincere developer base.
So, Android phone and iOS tablet. Unfortunately, they're not going to play too well together, but, that's what happens when you mix ecosystems. :)
I also have gone android phone and iPad. i think the Android tablets still need a little more time but at the rate they are improving hardware wise i think the the hardware will be much better than the iPad sooner rather than later but the software still seems to need 6 to 12 more months.
I tink they will play better together than you would think in regards to the music service and the e-mail accounts. i can have a mobile me account on the Droid. Wih the new iCloud service only seeming to support the "DRM" free music i can still synch that to my droid and since they don't seem to have a streaming service (yet) thats not an issue.
I'm doing the android / iPad2 combo right now and I really don't see a place for a mixed ecosystem. The android tablet scene seems just a little bit too immature right now but when you are a heavy drinker of the Google kool-aid, the iPad experience just isn't that pleasurable. If I'm reading on the device, I'm likely to be using the Kindle app. So, for that functionality, I'm platform agnostic. However, gTalk and gMail options on the iPad aren't very fun either. I guess I can't win.
So to answer the original question... this is a tough first-world problem. If I was starting from scratch, I would probably stay with an android phone and iPad. For my own purposes, the iPad doesn't gel with the way I'd like to use it as a communication device, however, that is only a small part of the equation. I suppose that the current content in the iPad app store has it beating the android tablets in all other categories.
At the moment I'm doing Android phone + iPad, and feel like that's the right combination – for now. iOS currently has a much more polished experience and better selection of apps targeted specifically for the tablet form factor.
That said... I could definitely see myself switching to iPhone + Android tablet in 1-2 years. Why?
* Android's Sharing API rocks- you can easily share content between any two apps that support the API, so I can easily send, say, pictures, to Dropbox... Picplz... Facebook... any app I like. iOS 5's Twitter integration shows that they're taking a more mainstream approach to this kind of sharing, which takes place on Apple-selected apps and networks. I constantly find myself wishing my iPad had Android's sharability.
* Android's browser is far behind MobileSafari in terms of rendering quality and feature support. I can't believe I'm saying that considering it comes from the same company as Chrome, but the Android and Chrome teams really haven't integrated their work much. It'll be a while before I'll be ready to give up MobileSafari on a tablet, which I find myself using much more heavily on a tablet than a smartphone.
Well maybe it's cause I'm using a Nexus phone, but I would do Android phone and iPad, but mostly just for the wifi tethering. Free tethering means wifi only iPad, which makes it cheaper, and no monthly fee for tethering, like it would on iPhone.
Yes I know I'm a wimp and don't jailbreak, or root my devices.
Android smartphone and iPad. The Android Gmail app is a big deal to me. I do a lot of mobile emailing. The iPad is used mostly for entertainment...and Netflix, Hulu, and the game selection on the iPad is a bajillion times better than what Honeycomb offers right now.
I already do that, HTC Evo 4G and an iPad 2...soon to be Evo 3D. Apple products hold value well so I sell back my iPad every year to get a new model while taking advantage of the cutting edge Android phones (as well as unlimited data/hotspot on Sprint:D)